diff --git a/pom.xml b/pom.xml
index f346295e9..4552ff7a3 100644
--- a/pom.xml
+++ b/pom.xml
@@ -16,7 +16,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>2.3.12.RELEASE</version>
+		<version>2.4.13</version>
 		<relativePath /> <!-- lookup parent from repository -->
 	</parent>
 
@@ -43,12 +43,12 @@
 		<javax.ws.rs-api.version>2.1.1</javax.ws.rs-api.version>
 		<spring-boot-starter-web.version>2.6.6</spring-boot-starter-web.version>
 		<spring-security-core.version>5.7.5</spring-security-core.version>
-		<spring-beans.version>5.2.20.RELEASE</spring-beans.version>
-		<spring-webmvc.version>5.2.20.RELEASE</spring-webmvc.version>
-		<spring-core.version>5.2.20.RELEASE</spring-core.version>
+		<spring-beans.version>5.3.34</spring-beans.version>
+		<spring-webmvc.version>5.3.34</spring-webmvc.version>
+		<spring-core.version>5.3.34</spring-core.version>
 		<json-smart.version>2.4.7</json-smart.version>
 		<springfox-swagger-ui.version>2.10.0</springfox-swagger-ui.version>
-		<spring-context-support.version>5.3.23</spring-context-support.version>
+		<spring-context-support.version>5.3.34</spring-context-support.version>
 		<ehcache.version>2.10.9.2</ehcache.version>
 		<testcontainers.version>1.17.6</testcontainers.version>
 	</properties>
@@ -64,6 +64,15 @@
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-security</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework</groupId>
+			<artifactId>spring-web</artifactId>
+			<version>5.3.34</version>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-validation</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-data-jpa</artifactId>
@@ -131,7 +140,7 @@
 		<dependency>
 			<groupId>org.hibernate</groupId>
 			<artifactId>hibernate-search-orm</artifactId>
-			<version>5.11.10.Final</version>
+			<version>5.11.12.Final</version>
 		</dependency>
 
 		<!-- Swagger/OpenAPI dependencies -->
@@ -158,6 +167,10 @@
 			<artifactId>springfox-swagger2</artifactId>
 			<version>${springfox.version}</version>
 		</dependency>
+		<dependency>
+			<groupId>javax.validation</groupId>
+			<artifactId>validation-api</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>io.springfox</groupId>
 			<artifactId>springfox-bean-validators</artifactId>
@@ -349,6 +362,12 @@
 			<groupId>org.powermock</groupId>
 			<scope>test</scope>
 			<version>${powermock.version}</version>
+			<exclusions>
+				<exclusion>
+					<groupId>junit</groupId>
+					<artifactId>junit</artifactId>
+				</exclusion>
+			</exclusions>
 		</dependency>
 		<dependency>
 			<artifactId>powermock-api-mockito2</artifactId>
@@ -457,6 +476,23 @@
 				<groupId>org.springframework.boot</groupId>
 				<artifactId>spring-boot-maven-plugin</artifactId>
 			</plugin>
+			<plugin>
+				<groupId>org.openrewrite.maven</groupId>
+				<artifactId>rewrite-maven-plugin</artifactId>
+				<version>5.30.0</version>
+				<configuration>
+					<activeRecipes>
+						<recipe>org.openrewrite.java.spring.boot2.UpgradeSpringBoot_2_4</recipe>
+					</activeRecipes>
+				</configuration>
+				<dependencies>
+					<dependency>
+						<groupId>org.openrewrite.recipe</groupId>
+						<artifactId>rewrite-spring</artifactId>
+						<version>5.9.0</version>
+					</dependency>
+				</dependencies>
+			</plugin>
 
 			<!--
               Add generated sources as source directory
diff --git a/src/main/java/de/caritas/cob/userservice/api/adapters/keycloak/KeycloakService.java b/src/main/java/de/caritas/cob/userservice/api/adapters/keycloak/KeycloakService.java
index 21759743d..7053319bc 100644
--- a/src/main/java/de/caritas/cob/userservice/api/adapters/keycloak/KeycloakService.java
+++ b/src/main/java/de/caritas/cob/userservice/api/adapters/keycloak/KeycloakService.java
@@ -55,7 +55,7 @@
 import org.springframework.stereotype.Service;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
-import org.springframework.util.StringUtils;
+import org.springframework.util.ObjectUtils;
 import org.springframework.web.client.HttpClientErrorException;
 import org.springframework.web.client.RestClientException;
 import org.springframework.web.client.RestClientResponseException;
@@ -617,7 +617,7 @@ private boolean hasEmailAddressChanged(UserResource userResource, String email)
     if (userRepresentation != null && userRepresentation.getEmail() != null) {
       return !userRepresentation.getEmail().equals(email);
     } else {
-      return !StringUtils.isEmpty(email);
+      return !ObjectUtils.isEmpty(email);
     }
   }
 
diff --git a/src/main/java/de/caritas/cob/userservice/api/adapters/rocketchat/RocketChatRollbackService.java b/src/main/java/de/caritas/cob/userservice/api/adapters/rocketchat/RocketChatRollbackService.java
index fbb9bafb5..3017c8fa9 100644
--- a/src/main/java/de/caritas/cob/userservice/api/adapters/rocketchat/RocketChatRollbackService.java
+++ b/src/main/java/de/caritas/cob/userservice/api/adapters/rocketchat/RocketChatRollbackService.java
@@ -6,7 +6,6 @@
 import de.caritas.cob.userservice.api.exception.rocketchat.RocketChatUserNotInitializedException;
 import java.util.List;
 import lombok.extern.slf4j.Slf4j;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 
 @Slf4j
@@ -16,7 +15,6 @@ public class RocketChatRollbackService {
   private final RocketChatService rocketChatService;
   private final RocketChatCredentialsProvider rcCredentialsHelper;
 
-  @Autowired
   public RocketChatRollbackService(
       RocketChatService rocketChatService, RocketChatCredentialsProvider rcCredentialsHelper) {
     this.rocketChatService = rocketChatService;
diff --git a/src/main/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminController.java b/src/main/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminController.java
index 5fb75aaf2..deac46cfa 100644
--- a/src/main/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminController.java
+++ b/src/main/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminController.java
@@ -171,8 +171,7 @@ public ResponseEntity<Void> deleteConsultantAgency(String consultantId, Long age
   @Override
   public ResponseEntity<Void> markConsultantForDeletion(
       @PathVariable String consultantId,
-      @Valid @RequestParam(value = "forceDeleteSessions", required = false)
-          Boolean forceDeleteSessions) {
+      @Valid @RequestParam(required = false) Boolean forceDeleteSessions) {
     this.consultantAdminFacade.markConsultantForDeletion(consultantId, forceDeleteSessions);
     return new ResponseEntity<>(HttpStatus.OK);
   }
diff --git a/src/main/java/de/caritas/cob/userservice/api/adapters/web/controller/UserController.java b/src/main/java/de/caritas/cob/userservice/api/adapters/web/controller/UserController.java
index 70d7547eb..4daed2a46 100644
--- a/src/main/java/de/caritas/cob/userservice/api/adapters/web/controller/UserController.java
+++ b/src/main/java/de/caritas/cob/userservice/api/adapters/web/controller/UserController.java
@@ -336,7 +336,7 @@ public ResponseEntity<UserSessionListResponseDTO> getSessionsForAuthenticatedUse
    */
   @Override
   public ResponseEntity<GroupSessionListResponseDTO> getSessionsForGroupOrFeedbackGroupIds(
-      @RequestHeader String rcToken, @RequestParam(value = "rcGroupIds") List<String> rcGroupIds) {
+      @RequestHeader String rcToken, @RequestParam List<String> rcGroupIds) {
     GroupSessionListResponseDTO groupSessionList;
     if (authenticatedUser.isConsultant()) {
       var consultant = userAccountProvider.retrieveValidatedConsultant();
diff --git a/src/main/java/de/caritas/cob/userservice/api/facade/sessionlist/RocketChatRoomInformationProvider.java b/src/main/java/de/caritas/cob/userservice/api/facade/sessionlist/RocketChatRoomInformationProvider.java
index af72cbaf4..176f894c2 100644
--- a/src/main/java/de/caritas/cob/userservice/api/facade/sessionlist/RocketChatRoomInformationProvider.java
+++ b/src/main/java/de/caritas/cob/userservice/api/facade/sessionlist/RocketChatRoomInformationProvider.java
@@ -15,7 +15,6 @@
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
 
 @Component
@@ -23,7 +22,6 @@ public class RocketChatRoomInformationProvider {
 
   private final RocketChatService rocketChatService;
 
-  @Autowired
   public RocketChatRoomInformationProvider(RocketChatService rocketChatService) {
     this.rocketChatService = requireNonNull(rocketChatService);
   }
diff --git a/src/main/java/de/caritas/cob/userservice/api/facade/sessionlist/SessionListFacade.java b/src/main/java/de/caritas/cob/userservice/api/facade/sessionlist/SessionListFacade.java
index cf8df1aef..52aa0f360 100644
--- a/src/main/java/de/caritas/cob/userservice/api/facade/sessionlist/SessionListFacade.java
+++ b/src/main/java/de/caritas/cob/userservice/api/facade/sessionlist/SessionListFacade.java
@@ -47,7 +47,6 @@ public class SessionListFacade {
   @Autowired(required = false)
   SessionTopicEnrichmentService sessionTopicEnrichmentService;
 
-  @Autowired
   public SessionListFacade(
       UserSessionListService userSessionListService,
       ConsultantSessionListService consultantSessionListService) {
diff --git a/src/main/java/de/caritas/cob/userservice/api/helper/SessionListAnalyser.java b/src/main/java/de/caritas/cob/userservice/api/helper/SessionListAnalyser.java
index 72155f6a6..51390877e 100644
--- a/src/main/java/de/caritas/cob/userservice/api/helper/SessionListAnalyser.java
+++ b/src/main/java/de/caritas/cob/userservice/api/helper/SessionListAnalyser.java
@@ -10,7 +10,6 @@
 import de.caritas.cob.userservice.api.service.DecryptionService;
 import de.caritas.cob.userservice.api.service.LogService;
 import java.util.Map;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
 
 /** Analyser methods for the session list. */
@@ -19,7 +18,6 @@ public class SessionListAnalyser {
 
   private final DecryptionService decryptionService;
 
-  @Autowired
   public SessionListAnalyser(DecryptionService decryptionService) {
     this.decryptionService = requireNonNull(decryptionService);
   }
diff --git a/src/main/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAskerRoomsAndSessionsAction.java b/src/main/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAskerRoomsAndSessionsAction.java
index 4db14b834..476e3ecf4 100644
--- a/src/main/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAskerRoomsAndSessionsAction.java
+++ b/src/main/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAskerRoomsAndSessionsAction.java
@@ -6,7 +6,6 @@
 import de.caritas.cob.userservice.api.port.out.SessionDataRepository;
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
 import de.caritas.cob.userservice.api.workflow.delete.model.AskerDeletionWorkflowDTO;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
 
 /** Delete action for sessions and Rocket.Chat rooms of a {@link User}. */
@@ -14,7 +13,6 @@
 public class DeleteAskerRoomsAndSessionsAction extends DeleteRoomsAndSessionAction
     implements ActionCommand<AskerDeletionWorkflowDTO> {
 
-  @Autowired
   public DeleteAskerRoomsAndSessionsAction(
       SessionRepository sessionRepository,
       SessionDataRepository sessionDataRepository,
diff --git a/src/main/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteSingleRoomAndSessionAction.java b/src/main/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteSingleRoomAndSessionAction.java
index e62d8f6d1..41c0b45d6 100644
--- a/src/main/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteSingleRoomAndSessionAction.java
+++ b/src/main/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteSingleRoomAndSessionAction.java
@@ -6,7 +6,6 @@
 import de.caritas.cob.userservice.api.port.out.SessionDataRepository;
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
 import de.caritas.cob.userservice.api.workflow.delete.model.SessionDeletionWorkflowDTO;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
 
 @Component
@@ -20,7 +19,6 @@ public class DeleteSingleRoomAndSessionAction extends DeleteRoomsAndSessionActio
    * @param sessionDataRepository a {@link SessionDataRepository} instance
    * @param rocketChatService a {@link RocketChatService} instance
    */
-  @Autowired
   public DeleteSingleRoomAndSessionAction(
       SessionRepository sessionRepository,
       SessionDataRepository sessionDataRepository,
diff --git a/src/main/resources/application.properties b/src/main/resources/application.properties
index 0725bd578..6593065a0 100644
--- a/src/main/resources/application.properties
+++ b/src/main/resources/application.properties
@@ -18,7 +18,7 @@ anonymous.username.prefix=Ratsuchende_r
 registration.cors.allowed.origins=
 registration.cors.allowed.paths=
 
-spring.mvc.locale=de_DE
+spring.web.locale=de_DE
 spring.jackson.time-zone=Europe/Berlin
 
 service.encryption.appkey=
@@ -209,5 +209,5 @@ feature.multitenancy.with.single.domain.enabled=false
 management.endpoint.health.enabled=true
 management.endpoint.health.show-details=never
 management.endpoints.web.exposure.include=health
-management.health.probes.enabled=true
+management.endpoint.health.probes.enabled=true
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/keycloak/KeycloakServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/keycloak/KeycloakServiceTest.java
index 748206202..e833eb76a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/keycloak/KeycloakServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/keycloak/KeycloakServiceTest.java
@@ -11,12 +11,7 @@
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
-import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
@@ -51,10 +46,10 @@
 import javax.ws.rs.core.Response;
 import org.apache.commons.lang3.RandomStringUtils;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
 import org.junit.jupiter.api.Assertions;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.keycloak.admin.client.resource.RealmResource;
 import org.keycloak.admin.client.resource.RoleMappingResource;
 import org.keycloak.admin.client.resource.RoleResource;
@@ -70,7 +65,9 @@
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 import org.slf4j.Logger;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
@@ -78,7 +75,8 @@
 import org.springframework.web.client.RestClientResponseException;
 import org.springframework.web.client.RestTemplate;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
 public class KeycloakServiceTest {
 
   private final String USER_ID = "asdh89sdfsjodifjsdf";
@@ -108,7 +106,7 @@ public class KeycloakServiceTest {
 
   EasyRandom easyRandom = new EasyRandom();
 
-  @Before
+  @BeforeEach
   public void setup() throws NoSuchFieldException, SecurityException {
     givenAKeycloakLoginUrl();
     givenAKeycloakLogoutUrl();
@@ -164,7 +162,7 @@ public void loginUser_Should_ReturnBadRequest_When_KeycloakLoginFails() {
       keycloakService.loginUser(USER_ID, OLD_PW);
       fail("Expected exception: BadRequestException");
     } catch (BadRequestException badRequestException) {
-      assertTrue("Excepted BadRequestException thrown", true);
+      assertTrue(true, "Excepted BadRequestException thrown");
     }
   }
 
@@ -285,13 +283,17 @@ public void getOtpCredential_Should_Return_Response_When_RequestWasSuccessful()
     assertEquals(OTP_INFO_DTO, keycloakService.getOtpCredential(USERNAME));
   }
 
-  @Test(expected = RestClientException.class)
+  @Test
   public void getOtpCredential_Should_Throw_When_RequestHasAnError() {
-    when(keycloakClient.getBearerToken()).thenReturn(BEARER_TOKEN);
-    when(this.keycloakClient.get(any(), any(), any()))
-        .thenThrow(new RestClientException("Fail test case"));
+    assertThrows(
+        RestClientException.class,
+        () -> {
+          when(keycloakClient.getBearerToken()).thenReturn(BEARER_TOKEN);
+          when(this.keycloakClient.get(any(), any(), any()))
+              .thenThrow(new RestClientException("Fail test case"));
 
-    keycloakService.getOtpCredential(USERNAME);
+          keycloakService.getOtpCredential(USERNAME);
+        });
   }
 
   @Test
@@ -454,18 +456,22 @@ public void createKeycloakUser_Should_createUserWithDefaultLocale() {
     }
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void createKeycloakUser_Should_ThrowInternalServerException_When_errorIsUnknown() {
-    UsersResource usersResource = mock(UsersResource.class);
-    Response response = mock(Response.class);
-    when(usersResource.create(any())).thenReturn(response);
-    ErrorRepresentation errorRepresentation = mock(ErrorRepresentation.class);
-    when(errorRepresentation.getErrorMessage()).thenReturn("error");
-    when(response.readEntity(ErrorRepresentation.class)).thenReturn(errorRepresentation);
-    when(keycloakClient.getUsersResource()).thenReturn(usersResource);
-    UserDTO userDTO = new EasyRandom().nextObject(UserDTO.class);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          UsersResource usersResource = mock(UsersResource.class);
+          Response response = mock(Response.class);
+          when(usersResource.create(any())).thenReturn(response);
+          ErrorRepresentation errorRepresentation = mock(ErrorRepresentation.class);
+          when(errorRepresentation.getErrorMessage()).thenReturn("error");
+          when(response.readEntity(ErrorRepresentation.class)).thenReturn(errorRepresentation);
+          when(keycloakClient.getUsersResource()).thenReturn(usersResource);
+          UserDTO userDTO = new EasyRandom().nextObject(UserDTO.class);
 
-    this.keycloakService.createKeycloakUser(userDTO);
+          this.keycloakService.createKeycloakUser(userDTO);
+        });
   }
 
   @Test
@@ -522,28 +528,33 @@ public void isUsernameAvailable_Should_returnFalse_When_EncodedUsernameIsNotAvai
     assertThat(isAvailable, is(false));
   }
 
-  @Test(expected = KeycloakException.class)
+  @Test
   public void updateRole_Should_throwKeycloakException_When_roleCouldNotBeUpdated() {
-    UserResource userResource = mock(UserResource.class);
-    UsersResource usersResource = mock(UsersResource.class);
-    when(usersResource.get(anyString())).thenReturn(userResource);
-    RoleScopeResource roleScopeResource = mock(RoleScopeResource.class);
-    RoleMappingResource roleMappingResource = mock(RoleMappingResource.class);
-    when(roleMappingResource.realmLevel()).thenReturn(roleScopeResource);
-    when(userResource.roles()).thenReturn(roleMappingResource);
-
-    RoleRepresentation roleRepresentation = new EasyRandom().nextObject(RoleRepresentation.class);
-    RoleResource roleResource = mock(RoleResource.class);
-    when(roleResource.toRepresentation()).thenReturn(roleRepresentation);
-    RolesResource rolesResource = mock(RolesResource.class);
-    when(rolesResource.get(any())).thenReturn(roleResource);
-
-    RealmResource realmResource = mock(RealmResource.class);
-    when(realmResource.users()).thenReturn(usersResource);
-    when(realmResource.roles()).thenReturn(rolesResource);
-    when(keycloakClient.getRealmResource()).thenReturn(realmResource);
-
-    this.keycloakService.updateRole("user", "role");
+    assertThrows(
+        KeycloakException.class,
+        () -> {
+          UserResource userResource = mock(UserResource.class);
+          UsersResource usersResource = mock(UsersResource.class);
+          when(usersResource.get(anyString())).thenReturn(userResource);
+          RoleScopeResource roleScopeResource = mock(RoleScopeResource.class);
+          RoleMappingResource roleMappingResource = mock(RoleMappingResource.class);
+          when(roleMappingResource.realmLevel()).thenReturn(roleScopeResource);
+          when(userResource.roles()).thenReturn(roleMappingResource);
+
+          RoleRepresentation roleRepresentation =
+              new EasyRandom().nextObject(RoleRepresentation.class);
+          RoleResource roleResource = mock(RoleResource.class);
+          when(roleResource.toRepresentation()).thenReturn(roleRepresentation);
+          RolesResource rolesResource = mock(RolesResource.class);
+          when(rolesResource.get(any())).thenReturn(roleResource);
+
+          RealmResource realmResource = mock(RealmResource.class);
+          when(realmResource.users()).thenReturn(usersResource);
+          when(realmResource.roles()).thenReturn(rolesResource);
+          when(keycloakClient.getRealmResource()).thenReturn(realmResource);
+
+          this.keycloakService.updateRole("user", "role");
+        });
   }
 
   @Test
@@ -773,13 +784,17 @@ public void userHasAuthority_Should_returnTrue_When_userHasAuthority() {
     assertThat(hasAuthority, is(true));
   }
 
-  @Test(expected = KeycloakException.class)
+  @Test
   public void userHasAuthority_Should_returnThrowKeycloakException_When_userHasNoRoles() {
-    UserResource userResource = mock(UserResource.class);
-    UsersResource usersResource = givenUsersResourceWithAnyUserId(userResource);
-    when(keycloakClient.getUsersResource()).thenReturn(usersResource);
-
-    this.keycloakService.userHasAuthority("user", "authority");
+    assertThrows(
+        KeycloakException.class,
+        () -> {
+          UserResource userResource = mock(UserResource.class);
+          UsersResource usersResource = givenUsersResourceWithAnyUserId(userResource);
+          when(keycloakClient.getUsersResource()).thenReturn(usersResource);
+
+          this.keycloakService.userHasAuthority("user", "authority");
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/rocketchat/dto/room/deserializer/AliasJsonDeserializerTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/rocketchat/dto/room/deserializer/AliasJsonDeserializerTest.java
index f3619311b..ebd21e1ce 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/rocketchat/dto/room/deserializer/AliasJsonDeserializerTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/rocketchat/dto/room/deserializer/AliasJsonDeserializerTest.java
@@ -5,8 +5,8 @@
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hamcrest.Matchers.nullValue;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
@@ -22,13 +22,13 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.util.ClassUtils;
 
-@RunWith(MockitoJUnitRunner.class)
-public class AliasJsonDeserializerTest {
+@ExtendWith(MockitoExtension.class)
+class AliasJsonDeserializerTest {
 
   private static final String DECODED_USERNAME = "username";
   private static final String ENCODE_USERNAME =
@@ -46,13 +46,12 @@ public class AliasJsonDeserializerTest {
   private final AliasJsonDeserializer aliasJsonDeserializer = new AliasJsonDeserializer();
 
   @Test
-  public void aliasJsonDeserializer_Should_haveNoArgsConstructor() {
+  void aliasJsonDeserializer_Should_haveNoArgsConstructor() {
     assertTrue(ClassUtils.hasConstructor(AliasJsonDeserializer.class));
   }
 
   @Test
-  public void deserialize_Should_convertAliasWithEncodedUsernameToForwardMessageDTO()
-      throws IOException {
+  void deserialize_Should_convertAliasWithEncodedUsernameToForwardMessageDTO() throws IOException {
     ForwardMessageDTO result =
         deserializeOldAliasJson(MESSAGE_FORWARD_ALIAS_JSON_WITH_ENCODED_USERNAME)
             .getForwardMessageDTO();
@@ -60,8 +59,7 @@ public void deserialize_Should_convertAliasWithEncodedUsernameToForwardMessageDT
   }
 
   @Test
-  public void deserialize_Should_convertAliasWithDecodedUsernameToForwardMessageDTO()
-      throws IOException {
+  void deserialize_Should_convertAliasWithDecodedUsernameToForwardMessageDTO() throws IOException {
     ForwardMessageDTO result =
         deserializeOldAliasJson(MESSAGE_FORWARD_ALIAS_JSON_WITH_DECODED_USERNAME)
             .getForwardMessageDTO();
@@ -69,13 +67,13 @@ public void deserialize_Should_convertAliasWithDecodedUsernameToForwardMessageDT
   }
 
   @Test
-  public void deserialize_Should_ReturnNull_IfAliasIsEmpty() throws IOException {
+  void deserialize_Should_ReturnNull_IfAliasIsEmpty() throws IOException {
     AliasMessageDTO result = deserializeOldAliasJson("");
     assertNull(result);
   }
 
   @Test
-  public void deserialize_Should_returnAliasDTOWithDecodedUsername_When_usernameIsEncoded()
+  void deserialize_Should_returnAliasDTOWithDecodedUsername_When_usernameIsEncoded()
       throws Exception {
     String aliasMessageDTO =
         asJsonString(
@@ -95,7 +93,7 @@ public void deserialize_Should_returnAliasDTOWithDecodedUsername_When_usernameIs
   }
 
   @Test
-  public void deserialize_Should_returnAliasDTOWithDecodedUsername_When_usernameIsDecoded()
+  void deserialize_Should_returnAliasDTOWithDecodedUsername_When_usernameIsDecoded()
       throws Exception {
     String aliasMessageDTO =
         asJsonString(
@@ -115,7 +113,7 @@ public void deserialize_Should_returnAliasDTOWithDecodedUsername_When_usernameIs
   }
 
   @Test
-  public void deserialize_Should_returnAliasDTOWithDecodedUsernames_When_usernamesAreEncoded()
+  void deserialize_Should_returnAliasDTOWithDecodedUsernames_When_usernamesAreEncoded()
       throws Exception {
     String aliasMessageDTO =
         asJsonString(
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/rocketchat/dto/room/deserializer/AliasMessageConverterTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/rocketchat/dto/room/deserializer/AliasMessageConverterTest.java
index b2e4bf130..1b870028a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/rocketchat/dto/room/deserializer/AliasMessageConverterTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/rocketchat/dto/room/deserializer/AliasMessageConverterTest.java
@@ -7,12 +7,12 @@
 import de.caritas.cob.userservice.api.adapters.web.dto.AliasMessageDTO;
 import de.caritas.cob.userservice.api.adapters.web.dto.ForwardMessageDTO;
 import java.util.Optional;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
-public class AliasMessageConverterTest {
+class AliasMessageConverterTest {
 
   @Test
-  public void
+  void
       convertStringToAliasMessageDTO_Should_returnOptionalEmpty_When_jsonStringCanNotBeConverted() {
     Optional<AliasMessageDTO> result =
         new AliasMessageConverter().convertStringToAliasMessageDTO("alias");
@@ -21,7 +21,7 @@ public class AliasMessageConverterTest {
   }
 
   @Test
-  public void
+  void
       convertStringToForwardMessageDTO_Should_returnOptionalEmpty_When_jsonStringCanNotBeConverted() {
     Optional<ForwardMessageDTO> result =
         new AliasMessageConverter().convertStringToForwardMessageDTO("alias");
@@ -30,7 +30,7 @@ public class AliasMessageConverterTest {
   }
 
   @Test
-  public void
+  void
       convertStringToAliasMessageDTO_Should_returnExpectedResult_When_jsonStringContainsMessageTypeFinishedConversation() {
     var result =
         new AliasMessageConverter()
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/ConversationControllerAuthorizationIT.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/ConversationControllerAuthorizationIT.java
index ca125f052..6a07c3788 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/ConversationControllerAuthorizationIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/ConversationControllerAuthorizationIT.java
@@ -40,8 +40,7 @@
 import de.caritas.cob.userservice.api.helper.UsernameTranscoder;
 import javax.servlet.http.Cookie;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
 import org.springframework.boot.test.context.SpringBootTest;
@@ -49,11 +48,9 @@
 import org.springframework.http.MediaType;
 import org.springframework.security.test.context.support.WithMockUser;
 import org.springframework.test.context.ActiveProfiles;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.web.servlet.MockMvc;
 import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
 
-@RunWith(SpringRunner.class)
 @ActiveProfiles("testing")
 @SpringBootTest
 @AutoConfigureMockMvc
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/ConversationControllerIT.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/ConversationControllerIT.java
index 965581758..89999be37 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/ConversationControllerIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/ConversationControllerIT.java
@@ -22,8 +22,7 @@
 import de.caritas.cob.userservice.api.helper.AuthenticatedUser;
 import de.caritas.cob.userservice.api.port.in.Messaging;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
 import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
@@ -31,10 +30,8 @@
 import org.springframework.hateoas.client.LinkDiscoverers;
 import org.springframework.http.MediaType;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.web.servlet.MockMvc;
 
-@RunWith(SpringRunner.class)
 @WebMvcTest(ConversationController.class)
 @AutoConfigureMockMvc(addFilters = false)
 @TestPropertySource(properties = "spring.profiles.active=testing")
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/LiveProxyControllerIT.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/LiveProxyControllerIT.java
index 4a7c84624..331a2ba55 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/LiveProxyControllerIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/LiveProxyControllerIT.java
@@ -9,18 +9,15 @@
 
 import de.caritas.cob.userservice.api.config.auth.RoleAuthorizationAuthorityMapper;
 import de.caritas.cob.userservice.api.service.liveevents.LiveEventNotificationService;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
 import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.hateoas.client.LinkDiscoverers;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.web.servlet.MockMvc;
 
-@RunWith(SpringRunner.class)
 @WebMvcTest(LiveProxyController.class)
 @AutoConfigureMockMvc(addFilters = false)
 @TestPropertySource(properties = "spring.profiles.active=testing")
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminControllerAuthorizationIT.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminControllerAuthorizationIT.java
index 499b05b80..db9e018ae 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminControllerAuthorizationIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminControllerAuthorizationIT.java
@@ -36,8 +36,7 @@
 import java.util.UUID;
 import javax.servlet.http.Cookie;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -47,10 +46,8 @@
 import org.springframework.http.MediaType;
 import org.springframework.security.test.context.support.WithMockUser;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.web.servlet.MockMvc;
 
-@RunWith(SpringRunner.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @SpringBootTest
 @AutoConfigureMockMvc
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminControllerIT.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminControllerIT.java
index 431df4403..7a45eadd9 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminControllerIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserAdminControllerIT.java
@@ -37,8 +37,7 @@
 import java.util.ArrayList;
 import java.util.UUID;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
@@ -48,10 +47,8 @@
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.hateoas.client.LinkDiscoverers;
 import org.springframework.http.MediaType;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.web.servlet.MockMvc;
 
-@RunWith(SpringRunner.class)
 @WebMvcTest(UserAdminController.class)
 @AutoConfigureMockMvc(addFilters = false)
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserControllerIT.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserControllerIT.java
index ce54c7bd2..7faea4871 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserControllerIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/UserControllerIT.java
@@ -8,7 +8,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.*;
 import static org.hamcrest.Matchers.is;
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.ArgumentMatchers.*;
 import static org.mockito.Mockito.*;
 import static org.powermock.reflect.Whitebox.setInternalState;
@@ -63,9 +63,8 @@
 import org.apache.commons.lang3.exception.ExceptionUtils;
 import org.hibernate.service.spi.ServiceException;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
 import org.mockito.Mockito;
@@ -79,14 +78,12 @@
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.web.servlet.MockMvc;
 
-@RunWith(SpringRunner.class)
 @WebMvcTest(UserController.class)
 @AutoConfigureMockMvc(addFilters = false)
 @TestPropertySource(properties = "spring.profiles.active=testing,feature.topics.enabled=true")
-public class UserControllerIT {
+class UserControllerIT {
 
   private static final Cookie RC_TOKEN_COOKIE =
       new Cookie("rc_token", RandomStringUtils.randomAlphanumeric(43));
@@ -353,8 +350,8 @@ public class UserControllerIT {
 
   @Mock private Chat chat;
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void setUp() {
     HashMap<String, Object> drugsMap = new HashMap<>();
     drugsMap.put("others", false);
     HashMap<String, Object> addictiveDrugsMap = new HashMap<>();
@@ -366,7 +363,7 @@ public void setUp() {
   }
 
   @Test
-  public void userExists_Should_Return404_When_UserDoesNotExist() throws Exception {
+  void userExists_Should_Return404_When_UserDoesNotExist() throws Exception {
     /* given */
     val username = "john@doe.com";
     when(identityClient.isUsernameAvailable(username)).thenReturn(Boolean.TRUE);
@@ -377,7 +374,7 @@ public void userExists_Should_Return404_When_UserDoesNotExist() throws Exception
   }
 
   @Test
-  public void userExists_Should_Return200_When_UserDoesExist() throws Exception {
+  void userExists_Should_Return200_When_UserDoesExist() throws Exception {
     /* given */
     val username = "john@doe.com";
     when(identityClient.isUsernameAvailable(username)).thenReturn(Boolean.FALSE);
@@ -390,7 +387,7 @@ public void userExists_Should_Return200_When_UserDoesExist() throws Exception {
 
   /** Method: registerUser */
   @Test
-  public void registerUser_Should_ReturnBadRequest_WhenProvidedWithInvalidRequestBody()
+  void registerUser_Should_ReturnBadRequest_WhenProvidedWithInvalidRequestBody()
       throws Exception {
 
     mvc.perform(
@@ -402,7 +399,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedWithInvalidRequestB
   }
 
   @Test
-  public void
+  void
       registerUser_Should_ReturnBadRequest_WhenProvidedWithConsultingTypeWithMandatoryFieldsAndInvalidAge()
           throws Exception {
 
@@ -418,7 +415,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedWithInvalidRequestB
   }
 
   @Test
-  public void
+  void
       registerUser_Should_ReturnBadRequest_WhenProvidedWithConsultingTypeWithMandatoryFieldsAndInvalidState()
           throws Exception {
 
@@ -438,7 +435,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedWithInvalidRequestB
   }
 
   @Test
-  public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooShort()
+  void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooShort()
       throws Exception {
 
     when(consultingTypeManager.getConsultingTypeSettings(0))
@@ -453,7 +450,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooShort(
   }
 
   @Test
-  public void
+  void
       activateTwoFactorAuthByApp_Should_NotActivateIfSingleTenantAdminButNotConfiguredToUse2Fa()
           throws Exception {
     when(authenticatedUser.isSingleTenantAdmin()).thenReturn(true);
@@ -469,7 +466,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooShort(
   }
 
   @Test
-  public void
+  void
       activateTwoFactorAuthByApp_Should_NotActivateIfTenantSuperAdminButNotConfiguredToUse2Fa()
           throws Exception {
     when(authenticatedUser.isTenantSuperAdmin()).thenReturn(true);
@@ -485,7 +482,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooShort(
   }
 
   @Test
-  public void activateTwoFactorAuthByApp_Should_Activate() throws Exception {
+  void activateTwoFactorAuthByApp_Should_Activate() throws Exception {
     when(authenticatedUser.getUsername()).thenReturn("username");
     when(identityManager.setUpOneTimePassword(anyString(), anyString(), anyString()))
         .thenReturn(true);
@@ -500,7 +497,7 @@ public void activateTwoFactorAuthByApp_Should_Activate() throws Exception {
   }
 
   @Test
-  public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooLong()
+  void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooLong()
       throws Exception {
 
     when(consultingTypeManager.getConsultingTypeSettings(0))
@@ -515,7 +512,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooLong()
   }
 
   @Test
-  public void
+  void
       registerUser_Should_ReturnCreated_WhenProvidedWithValidRequestBodyAndKeycloakResponseIsSuccessful()
           throws Exception {
     when(userHelper.isUsernameValid(anyString())).thenReturn(true);
@@ -535,7 +532,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooLong()
   }
 
   @Test
-  public void
+  void
       registerUser_Should_ReturnCreated_WhenProvidedWithValidU25RequestBodyAndKeycloakResponseIsSuccessful()
           throws Exception {
     when(userHelper.isUsernameValid(anyString())).thenReturn(true);
@@ -555,7 +552,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooLong()
   }
 
   @Test
-  public void
+  void
       registerUser_Should_ReturnConflict_WhenProvidedWithValidRequestBodyAndKeycloakResponseIsConflict()
           throws Exception {
     when(userHelper.isUsernameValid(anyString())).thenReturn(true);
@@ -578,7 +575,7 @@ public void registerUser_Should_ReturnBadRequest_WhenProvidedUsernameIsTooLong()
   }
 
   @Test
-  public void registerUser_Should_ReturnBadRequest_When_PostcodeIsMissing() throws Exception {
+  void registerUser_Should_ReturnBadRequest_When_PostcodeIsMissing() throws Exception {
 
     when(mandatoryFieldsProvider.fetchMandatoryFieldsForConsultingType(anyString()))
         .thenReturn(
@@ -596,7 +593,7 @@ public void registerUser_Should_ReturnBadRequest_When_PostcodeIsMissing() throws
   }
 
   @Test
-  public void registerUser_Should_ReturnBadRequest_When_PostcodeIsInvalid() throws Exception {
+  void registerUser_Should_ReturnBadRequest_When_PostcodeIsInvalid() throws Exception {
 
     when(mandatoryFieldsProvider.fetchMandatoryFieldsForConsultingType(anyString()))
         .thenReturn(
@@ -615,7 +612,7 @@ public void registerUser_Should_ReturnBadRequest_When_PostcodeIsInvalid() throws
 
   /** Method: registerNewConsultingType */
   @Test
-  public void
+  void
       registerNewConsultingType_Should_ReturnBadRequest_When_ProvidedWithInvalidRequestBody()
           throws Exception {
     mvc.perform(
@@ -629,7 +626,7 @@ public void registerUser_Should_ReturnBadRequest_When_PostcodeIsInvalid() throws
   }
 
   @Test
-  public void registerNewConsultingType_Should_ReturnBadRequest_When_PostcodeIsInvalid()
+  void registerNewConsultingType_Should_ReturnBadRequest_When_PostcodeIsInvalid()
       throws Exception {
     mvc.perform(
             post(PATH_POST_REGISTER_NEW_CONSULTING_TYPE)
@@ -642,7 +639,7 @@ public void registerNewConsultingType_Should_ReturnBadRequest_When_PostcodeIsInv
   }
 
   @Test
-  public void registerNewConsultingType_Should_ReturnBadRequest_When_PostcodeIsMissing()
+  void registerNewConsultingType_Should_ReturnBadRequest_When_PostcodeIsMissing()
       throws Exception {
     mvc.perform(
             post(PATH_POST_REGISTER_NEW_CONSULTING_TYPE)
@@ -655,7 +652,7 @@ public void registerNewConsultingType_Should_ReturnBadRequest_When_PostcodeIsMis
   }
 
   @Test
-  public void registerNewConsultingType_Should_ReturnBadRequest_When_AgencyIdMissing()
+  void registerNewConsultingType_Should_ReturnBadRequest_When_AgencyIdMissing()
       throws Exception {
     when(consultingTypeManager.getConsultingTypeSettings(any()))
         .thenReturn(CONSULTING_TYPE_SETTINGS_SUCHT);
@@ -671,7 +668,7 @@ public void registerNewConsultingType_Should_ReturnBadRequest_When_AgencyIdMissi
   }
 
   @Test
-  public void registerNewConsultingType_Should_ReturnBadRequest_When_ConsultingTypeMissing()
+  void registerNewConsultingType_Should_ReturnBadRequest_When_ConsultingTypeMissing()
       throws Exception {
     mvc.perform(
             post(PATH_POST_REGISTER_NEW_CONSULTING_TYPE)
@@ -684,7 +681,7 @@ public void registerNewConsultingType_Should_ReturnBadRequest_When_ConsultingTyp
   }
 
   @Test
-  public void registerNewConsultingType_Should_ReturnBadRequest_When_RcUserIdIsMissing()
+  void registerNewConsultingType_Should_ReturnBadRequest_When_RcUserIdIsMissing()
       throws Exception {
     mvc.perform(
             post(PATH_POST_REGISTER_NEW_CONSULTING_TYPE)
@@ -696,7 +693,7 @@ public void registerNewConsultingType_Should_ReturnBadRequest_When_RcUserIdIsMis
   }
 
   @Test
-  public void registerNewConsultingType_Should_ReturnBadRequest_When_RcTokenIsMissing()
+  void registerNewConsultingType_Should_ReturnBadRequest_When_RcTokenIsMissing()
       throws Exception {
     mvc.perform(
             post(PATH_POST_REGISTER_NEW_CONSULTING_TYPE)
@@ -708,7 +705,7 @@ public void registerNewConsultingType_Should_ReturnBadRequest_When_RcTokenIsMiss
   }
 
   @Test
-  public void registerNewConsultingTyp_Should_ReturnCreated_When_ProvidedWithValidRequestBody()
+  void registerNewConsultingTyp_Should_ReturnCreated_When_ProvidedWithValidRequestBody()
       throws Exception {
 
     when(accountProvider.retrieveValidatedUser()).thenReturn(USER);
@@ -730,7 +727,7 @@ public void registerNewConsultingTyp_Should_ReturnCreated_When_ProvidedWithValid
 
   /** Method: acceptEnquiry */
   @Test
-  public void acceptEnquiry_Should_ReturnInternalServerError_WhenNoConsultantInDbFound()
+  void acceptEnquiry_Should_ReturnInternalServerError_WhenNoConsultantInDbFound()
       throws Exception {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(SESSION));
@@ -749,7 +746,7 @@ public void acceptEnquiry_Should_ReturnInternalServerError_WhenNoConsultantInDbF
   }
 
   @Test
-  public void acceptEnquiry_Should_ReturnInternalServerError_WhenSessionNotFoundInDb()
+  void acceptEnquiry_Should_ReturnInternalServerError_WhenSessionNotFoundInDb()
       throws Exception {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.empty());
@@ -767,7 +764,7 @@ public void acceptEnquiry_Should_ReturnInternalServerError_WhenSessionNotFoundIn
   }
 
   @Test
-  public void acceptEnquiry_Should_ReturnInternalServerError_WhenSessionHasNoRocketChatGroupId()
+  void acceptEnquiry_Should_ReturnInternalServerError_WhenSessionHasNoRocketChatGroupId()
       throws Exception {
 
     when(sessionService.getSession(SESSION_ID))
@@ -786,7 +783,7 @@ public void acceptEnquiry_Should_ReturnInternalServerError_WhenSessionHasNoRocke
   }
 
   @Test
-  public void acceptEnquiry_Should_ReturnSuccess_WhenAcceptEnquiryIsSuccessfull() throws Exception {
+  void acceptEnquiry_Should_ReturnSuccess_WhenAcceptEnquiryIsSuccessfull() throws Exception {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(TEAM_SESSION));
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
@@ -801,7 +798,7 @@ public void acceptEnquiry_Should_ReturnSuccess_WhenAcceptEnquiryIsSuccessfull()
   }
 
   @Test
-  public void acceptEnquiry_Should_ReturnConflict_WhenEnquiryIsAlreadyAssigned() throws Exception {
+  void acceptEnquiry_Should_ReturnConflict_WhenEnquiryIsAlreadyAssigned() throws Exception {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(TEAM_SESSION));
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
@@ -819,7 +816,7 @@ public void acceptEnquiry_Should_ReturnConflict_WhenEnquiryIsAlreadyAssigned() t
   }
 
   @Test
-  public void
+  void
       acceptEnquiry_Should_ReturnInternalServerError_WhenAuthenticatedUserIsNotPresentInApplicationDb()
           throws Exception {
 
@@ -837,7 +834,7 @@ public void acceptEnquiry_Should_ReturnConflict_WhenEnquiryIsAlreadyAssigned() t
   }
 
   @Test
-  public void createEnquiryMessage_Should_ReturnConflict_WhenMessageIsAlreadyCreated()
+  void createEnquiryMessage_Should_ReturnConflict_WhenMessageIsAlreadyCreated()
       throws Exception {
 
     when(authenticatedUser.getUserId()).thenReturn(USER_ID);
@@ -857,7 +854,7 @@ public void createEnquiryMessage_Should_ReturnConflict_WhenMessageIsAlreadyCreat
   }
 
   @Test
-  public void createEnquiryMessage_Should_ReturnCreated_WhenMessageWasCreated() throws Exception {
+  void createEnquiryMessage_Should_ReturnCreated_WhenMessageWasCreated() throws Exception {
     when(authenticatedUser.getUserId()).thenReturn(USER_ID);
     when(accountProvider.retrieveValidatedUser()).thenReturn(USER);
     var expectedRCCredentials =
@@ -884,7 +881,7 @@ public void createEnquiryMessage_Should_ReturnCreated_WhenMessageWasCreated() th
   }
 
   @Test
-  public void
+  void
       createEnquiryMessage_Should_ReturnInternalServerError_WhenAuthenticatedUserIsNotPresentInApplicationDb()
           throws Exception {
 
@@ -903,7 +900,7 @@ public void createEnquiryMessage_Should_ReturnCreated_WhenMessageWasCreated() th
 
   /** Method: getSessionsForAuthenticatedUser (role: user) */
   @Test
-  public void getSessionsForAuthenticatedUser_Should_ReturnUserSessionsAndOk_WhenAuthorized()
+  void getSessionsForAuthenticatedUser_Should_ReturnUserSessionsAndOk_WhenAuthorized()
       throws Exception {
 
     List<UserSessionResponseDTO> sessions = new ArrayList<>();
@@ -937,7 +934,7 @@ public void getSessionsForAuthenticatedUser_Should_ReturnUserSessionsAndOk_WhenA
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedUser_Should_ReturnInternalServerError_WhenAuthorizedButUserNotFound()
           throws Exception {
 
@@ -956,7 +953,7 @@ public void getSessionsForAuthenticatedUser_Should_ReturnUserSessionsAndOk_WhenA
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedUser_Should_ReturnNoContent_WhenAuthorizedAndNoOpenSessionsAvailableAndSessionListIsEmpty()
           throws Exception {
     List<UserSessionResponseDTO> session = new ArrayList<>();
@@ -977,7 +974,7 @@ public void getSessionsForAuthenticatedUser_Should_ReturnUserSessionsAndOk_WhenA
   }
 
   @Test
-  public void getSessionsForAuthenticatedUser_Should_ReturnBadRequest_WhenHeaderParamIsMissing()
+  void getSessionsForAuthenticatedUser_Should_ReturnBadRequest_WhenHeaderParamIsMissing()
       throws Exception {
 
     mvc.perform(
@@ -988,7 +985,7 @@ public void getSessionsForAuthenticatedUser_Should_ReturnBadRequest_WhenHeaderPa
   }
 
   @Test
-  public void updateAbsence_Should_ReturnOk_When_Saved() throws Exception {
+  void updateAbsence_Should_ReturnOk_When_Saved() throws Exception {
 
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
     when(accountProvider.retrieveValidatedTeamConsultant()).thenReturn(TEAM_CONSULTANT);
@@ -1003,7 +1000,7 @@ public void updateAbsence_Should_ReturnOk_When_Saved() throws Exception {
   }
 
   @Test
-  public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() throws Exception {
+  void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() throws Exception {
     mvc.perform(
             put(PATH_PUT_CONSULTANT_ABSENT)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -1013,7 +1010,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
 
   /** Method: getSessionsForAuthenticatedConsultant (role: consultant) */
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenStatusParamIsMissing()
           throws Exception {
     mvc.perform(
@@ -1027,7 +1024,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnUnauthorized_WhenUnauthorizedExceptionIsRaised()
           throws Exception {
     var runtimeException = easyRandom.nextObject(RuntimeException.class);
@@ -1052,7 +1049,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenHeaderParamIsMissing()
           throws Exception {
     mvc.perform(
@@ -1065,7 +1062,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnInternalServerError_WhenNoConsultantInDbFound()
           throws Exception {
 
@@ -1082,7 +1079,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnSuccess_WhenAuthorizedAndSessionAvailable()
           throws Exception {
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
@@ -1097,7 +1094,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnNoContent_WhenAuthorizedAndNoSessionsAvailable()
           throws Exception {
 
@@ -1113,7 +1110,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnNoContent_WhenAuthorizedAndSessionListIsEmpty()
           throws Exception {
 
@@ -1129,7 +1126,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenParamOffestIsMissing()
           throws Exception {
 
@@ -1142,7 +1139,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenParamOffestHasANegativeValue()
           throws Exception {
 
@@ -1155,7 +1152,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenParamCountIsMissing()
           throws Exception {
 
@@ -1168,7 +1165,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenParamCountHasANegativeValue()
           throws Exception {
 
@@ -1181,7 +1178,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void
+  void
       getSessionsForAuthenticatedConsultant_Should_ReturnNotContent_WhenFilterParamIsInvalid()
           throws Exception {
 
@@ -1198,7 +1195,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
 
   /** Method: getUserData (role: consultant / user) */
   @Test
-  public void
+  void
       getUserData_ForUser_Should_ReturnInternalServerError_WhenAuthenticatedUserIsNotPresentInApplicationDb()
           throws Exception {
 
@@ -1217,7 +1214,7 @@ public void updateAbsence_Should_ReturnBadRequest_When_RequestBodyIsMissing() th
   }
 
   @Test
-  public void getUserData_ForSingleTenantAdmin_Should_ReturnUserDataFromKeycloak()
+  void getUserData_ForSingleTenantAdmin_Should_ReturnUserDataFromKeycloak()
       throws Exception {
     when(authenticatedUser.isSingleTenantAdmin()).thenReturn(true);
     when(keycloakUserDataProvider.retrieveAuthenticatedUserData())
@@ -1232,7 +1229,7 @@ public void getUserData_ForSingleTenantAdmin_Should_ReturnUserDataFromKeycloak()
   }
 
   @Test
-  public void getUserData_ForTenantSuperAdmin_Should_ReturnUserDataFromKeycloak() throws Exception {
+  void getUserData_ForTenantSuperAdmin_Should_ReturnUserDataFromKeycloak() throws Exception {
     when(authenticatedUser.isTenantSuperAdmin()).thenReturn(true);
     when(keycloakUserDataProvider.retrieveAuthenticatedUserData())
         .thenReturn(new UserDataResponseDTO());
@@ -1246,7 +1243,7 @@ public void getUserData_ForTenantSuperAdmin_Should_ReturnUserDataFromKeycloak()
   }
 
   @Test
-  public void getUserData_ForAgencySuperAdmin_Should_ReturnUserDataFromKeycloak() throws Exception {
+  void getUserData_ForAgencySuperAdmin_Should_ReturnUserDataFromKeycloak() throws Exception {
     when(authenticatedUser.isAgencySuperAdmin()).thenReturn(true);
     when(keycloakUserDataProvider.retrieveAuthenticatedUserData())
         .thenReturn(new UserDataResponseDTO());
@@ -1260,7 +1257,7 @@ public void getUserData_ForAgencySuperAdmin_Should_ReturnUserDataFromKeycloak()
   }
 
   @Test
-  public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeycloak()
+  void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeycloak()
       throws Exception {
     when(authenticatedUser.isRestrictedAgencyAdmin()).thenReturn(true);
     when(keycloakUserDataProvider.retrieveAuthenticatedUserData())
@@ -1276,7 +1273,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
 
   /** Method: getTeamSessionsForAuthenticatedConsultant (role: consultant) */
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenHeaderParamIsMissing()
           throws Exception {
 
@@ -1288,7 +1285,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnInternalServerError_WhenNoConsultantInDbFound()
           throws Exception {
 
@@ -1305,7 +1302,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnForbidden_WhenConsultantIsNoTeamConsultant()
           throws Exception {
 
@@ -1323,7 +1320,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnNoContent_WhenAuthorizedAndNoSessionsAvailable()
           throws Exception {
 
@@ -1339,7 +1336,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnSucess_WhenAuthorizedAndSessionsAvailable()
           throws Exception {
 
@@ -1355,7 +1352,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenParamOffestIsMissing()
           throws Exception {
     mvc.perform(
@@ -1367,7 +1364,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenParamOffestHasANegativeValue()
           throws Exception {
     mvc.perform(
@@ -1379,7 +1376,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenParamCountIsMissing()
           throws Exception {
     mvc.perform(
@@ -1391,7 +1388,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnBadRequest_WhenParamCountHasANegativeValue()
           throws Exception {
     mvc.perform(
@@ -1403,7 +1400,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
   }
 
   @Test
-  public void
+  void
       getTeamSessionsForAuthenticatedConsultant_Should_ReturnNotContent_WhenFilterParamIsInvalid()
           throws Exception {
 
@@ -1420,7 +1417,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
 
   /** sendNewMessageNotification() */
   @Test
-  public void
+  void
       sendNewMessageNotification_Should_CallEmailNotificationFacadeAndReturn2xxSuccessful_WhenCalled()
           throws Exception {
     var validNewMessageRequestBody = "{\"rcGroupId\": \"" + RC_GROUP_ID + "\"}";
@@ -1438,7 +1435,7 @@ public void getUserData_ForRestrictedAgencyAdmin_Should_ReturnUserDataFromKeyclo
 
   /** Method: getConsultants (authority: VIEW_AGENCY_CONSULTANTS) */
   @Test
-  public void getConsultants_Should_ReturnBadRequest_WhenQueryParamIsMissing() throws Exception {
+  void getConsultants_Should_ReturnBadRequest_WhenQueryParamIsMissing() throws Exception {
 
     mvc.perform(
             get(PATH_GET_CONSULTANTS_FOR_AGENCY_WITHOUT_PARAM)
@@ -1448,7 +1445,7 @@ public void getConsultants_Should_ReturnBadRequest_WhenQueryParamIsMissing() thr
   }
 
   @Test
-  public void getConsultants_Should_ReturnNoContent_WhenNoConsultantInDbFound() throws Exception {
+  void getConsultants_Should_ReturnNoContent_WhenNoConsultantInDbFound() throws Exception {
 
     mvc.perform(
             get(PATH_GET_CONSULTANTS_FOR_AGENCY)
@@ -1458,7 +1455,7 @@ public void getConsultants_Should_ReturnNoContent_WhenNoConsultantInDbFound() th
   }
 
   @Test
-  public void
+  void
       getConsultants_Should_ReturnInternalServerError_WhenConsultantAgencyServiceThrowsException()
           throws Exception {
 
@@ -1473,7 +1470,7 @@ public void getConsultants_Should_ReturnNoContent_WhenNoConsultantInDbFound() th
   }
 
   @Test
-  public void
+  void
       getConsultants_Should_ReturnOkAndValidContent_WhenConsultantAgencyServiceReturnsListWithEntries()
           throws Exception {
 
@@ -1498,7 +1495,7 @@ public void getConsultants_Should_ReturnNoContent_WhenNoConsultantInDbFound() th
 
   /** Method: assignSession (role: consultant) */
   @Test
-  public void assignSession_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws Exception {
+  void assignSession_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws Exception {
 
     mvc.perform(
             put(PATH_PUT_ASSIGN_SESSION_INVALID_PARAMS)
@@ -1508,7 +1505,7 @@ public void assignSession_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() th
   }
 
   @Test
-  public void
+  void
       assignSession_Should_ReturnInternalServerErrorAndLogError_WhenSessionServiceThrowsException()
           throws Exception {
 
@@ -1524,7 +1521,7 @@ public void assignSession_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() th
   }
 
   @Test
-  public void assignSession_Should_ReturnHttpStatusOfAssignSessionFacade() throws Exception {
+  void assignSession_Should_ReturnHttpStatusOfAssignSessionFacade() throws Exception {
 
     when(accountProvider.retrieveValidatedConsultantById(any())).thenReturn(TEAM_CONSULTANT);
     when(sessionService.getSession(Mockito.anyLong())).thenReturn(Optional.of(SESSION));
@@ -1544,7 +1541,7 @@ public void assignSession_Should_ReturnHttpStatusOfAssignSessionFacade() throws
   }
 
   @Test
-  public void
+  void
       assignSession_Should_ReturnInternalServerErrorAndLogError_WhenConsultantIsNotFoundInDb()
           throws Exception {
 
@@ -1561,7 +1558,7 @@ public void assignSession_Should_ReturnHttpStatusOfAssignSessionFacade() throws
   }
 
   @Test
-  public void assignSession_Should_ReturnInternalServerErrorAndLogError_WhenSessionIsNotFoundInDb()
+  void assignSession_Should_ReturnInternalServerErrorAndLogError_WhenSessionIsNotFoundInDb()
       throws Exception {
 
     when(accountProvider.retrieveValidatedConsultant()).thenReturn(TEAM_CONSULTANT);
@@ -1577,7 +1574,7 @@ public void assignSession_Should_ReturnInternalServerErrorAndLogError_WhenSessio
   }
 
   @Test
-  public void
+  void
       assignSession_Should_ReturnForbiddenAndLogError_WhenCallerDoesNotHaveTheRightToAssignEnquiries()
           throws Exception {
 
@@ -1596,7 +1593,7 @@ public void assignSession_Should_ReturnInternalServerErrorAndLogError_WhenSessio
   }
 
   @Test
-  public void registerUser_Should_DecodePassword() throws Exception {
+  void registerUser_Should_DecodePassword() throws Exception {
     when(userHelper.isUsernameValid(anyString())).thenReturn(true);
     when(mandatoryFieldsProvider.fetchMandatoryFieldsForConsultingType(anyString()))
         .thenReturn(
@@ -1620,7 +1617,7 @@ public void registerUser_Should_DecodePassword() throws Exception {
 
   /** updatePassword() */
   @Test
-  public void updatePassword_Should_ReturnBadRequest_When_PasswordsAreMissing() throws Exception {
+  void updatePassword_Should_ReturnBadRequest_When_PasswordsAreMissing() throws Exception {
 
     mvc.perform(
             put(PATH_PUT_UPDATE_PASSWORD)
@@ -1632,7 +1629,7 @@ public void updatePassword_Should_ReturnBadRequest_When_PasswordsAreMissing() th
   }
 
   @Test
-  public void updateKey_Should_ReturnConflict_WhenProvidedWithSameKey() throws Exception {
+  void updateKey_Should_ReturnConflict_WhenProvidedWithSameKey() throws Exception {
 
     when(encryptionService.getMasterKey()).thenReturn(MASTER_KEY_1);
 
@@ -1645,7 +1642,7 @@ public void updateKey_Should_ReturnConflict_WhenProvidedWithSameKey() throws Exc
   }
 
   @Test
-  public void updateKey_Should_ReturnAccepted_WhenProvidedWithNewKey() throws Exception {
+  void updateKey_Should_ReturnAccepted_WhenProvidedWithNewKey() throws Exception {
 
     when(encryptionService.getMasterKey()).thenReturn(MASTER_KEY_1);
 
@@ -1658,7 +1655,7 @@ public void updateKey_Should_ReturnAccepted_WhenProvidedWithNewKey() throws Exce
   }
 
   @Test
-  public void createChat_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws Exception {
+  void createChat_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws Exception {
 
     mvc.perform(
             post(PATH_POST_CHAT_NEW)
@@ -1671,7 +1668,7 @@ public void createChat_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throw
   }
 
   @Test
-  public void createChat_Should_ReturnInternalServerErrorAndLogError_When_ChatCouldNotBeCreated()
+  void createChat_Should_ReturnInternalServerErrorAndLogError_When_ChatCouldNotBeCreated()
       throws Exception {
 
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
@@ -1698,7 +1695,7 @@ private String giveValidCreateChatBodyWithAgencyId(Long agencyId) {
   }
 
   @Test
-  public void createChat_Should_ReturnCreated_When_ChatWasCreated() throws Exception {
+  void createChat_Should_ReturnCreated_When_ChatWasCreated() throws Exception {
 
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
     when(accountProvider.retrieveValidatedConsultant()).thenReturn(TEAM_CONSULTANT);
@@ -1714,7 +1711,7 @@ public void createChat_Should_ReturnCreated_When_ChatWasCreated() throws Excepti
   }
 
   @Test
-  public void createChatV2_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws Exception {
+  void createChatV2_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws Exception {
 
     mvc.perform(
             post(PATH_POST_CHAT_NEW_V2)
@@ -1727,7 +1724,7 @@ public void createChatV2_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() thr
   }
 
   @Test
-  public void createChatV2_Should_ReturnInternalServerErrorAndLogError_When_ChatCouldNotBeCreated()
+  void createChatV2_Should_ReturnInternalServerErrorAndLogError_When_ChatCouldNotBeCreated()
       throws Exception {
 
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
@@ -1744,7 +1741,7 @@ public void createChatV2_Should_ReturnInternalServerErrorAndLogError_When_ChatCo
   }
 
   @Test
-  public void createChatV2_Should_ReturnCreated_When_ChatWasCreated() throws Exception {
+  void createChatV2_Should_ReturnCreated_When_ChatWasCreated() throws Exception {
 
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
     when(accountProvider.retrieveValidatedConsultant()).thenReturn(TEAM_CONSULTANT);
@@ -1761,7 +1758,7 @@ public void createChatV2_Should_ReturnCreated_When_ChatWasCreated() throws Excep
 
   /** Method: startChat */
   @Test
-  public void startChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
+  void startChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
 
     mvc.perform(
             put(PATH_PUT_CHAT_START_WITH_INVALID_PATH_PARAMS)
@@ -1776,7 +1773,7 @@ public void startChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws
   }
 
   @Test
-  public void startChat_Should_ReturnOK_When_ChatWasStarted() throws Exception {
+  void startChat_Should_ReturnOK_When_ChatWasStarted() throws Exception {
 
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
     when(accountProvider.retrieveValidatedConsultant()).thenReturn(TEAM_CONSULTANT);
@@ -1790,7 +1787,7 @@ public void startChat_Should_ReturnOK_When_ChatWasStarted() throws Exception {
   }
 
   @Test
-  public void startChat_Should_ReturnBadRequest_When_StartChatThrowsBadRequest() throws Exception {
+  void startChat_Should_ReturnBadRequest_When_StartChatThrowsBadRequest() throws Exception {
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
     when(chatService.getChat(Mockito.any())).thenReturn(Optional.empty());
 
@@ -1805,7 +1802,7 @@ public void startChat_Should_ReturnBadRequest_When_StartChatThrowsBadRequest() t
   }
 
   @Test
-  public void startChat_Should_ReturnBadRequest_When_ChatWasNotFound() throws Exception {
+  void startChat_Should_ReturnBadRequest_When_ChatWasNotFound() throws Exception {
 
     when(authenticatedUser.getUserId()).thenReturn(CONSULTANT_ID);
     when(accountProvider.retrieveValidatedConsultant())
@@ -1821,7 +1818,7 @@ public void startChat_Should_ReturnBadRequest_When_ChatWasNotFound() throws Exce
 
   /** Method: getChat */
   @Test
-  public void getChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
+  void getChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
 
     mvc.perform(
             get(PATH_GET_CHAT_WITH_INVALID_PATH_PARAMS)
@@ -1836,7 +1833,7 @@ public void getChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Ex
   }
 
   @Test
-  public void getChat_Should_ReturnOk_When_RequestOk() throws Exception {
+  void getChat_Should_ReturnOk_When_RequestOk() throws Exception {
 
     mvc.perform(
             get(PATH_GET_CHAT)
@@ -1848,7 +1845,7 @@ public void getChat_Should_ReturnOk_When_RequestOk() throws Exception {
   }
 
   @Test
-  public void assignChat_Should_ReturnOk_When_ChatWasAssigned() throws Exception {
+  void assignChat_Should_ReturnOk_When_ChatWasAssigned() throws Exception {
     mvc.perform(
             put(PATH_PUT_ASSIGN_CHAT)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -1860,7 +1857,7 @@ public void assignChat_Should_ReturnOk_When_ChatWasAssigned() throws Exception {
 
   /** Method: joinChat */
   @Test
-  public void joinChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
+  void joinChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
 
     mvc.perform(
             put(PATH_PUT_JOIN_CHAT_WITH_INVALID_PATH_PARAMS)
@@ -1875,7 +1872,7 @@ public void joinChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws E
   }
 
   @Test
-  public void joinChat_Should_ReturnOk_When_ChatWasJoined() throws Exception {
+  void joinChat_Should_ReturnOk_When_ChatWasJoined() throws Exception {
 
     mvc.perform(
             put(PATH_PUT_JOIN_CHAT)
@@ -1887,7 +1884,7 @@ public void joinChat_Should_ReturnOk_When_ChatWasJoined() throws Exception {
   }
 
   @Test
-  public void stopChat_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws Exception {
+  void stopChat_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws Exception {
 
     mvc.perform(
             put(PATH_PUT_CHAT_STOP_INVALID)
@@ -1901,7 +1898,7 @@ public void stopChat_Should_ReturnBadRequest_WhenQueryParamsAreInvalid() throws
   }
 
   @Test
-  public void stopChat_Should_ReturnInternalServerError_When_CallingConsultantDoesNotExist()
+  void stopChat_Should_ReturnInternalServerError_When_CallingConsultantDoesNotExist()
       throws Exception {
 
     when(chatService.getChat(any())).thenReturn(Optional.of(mock(Chat.class)));
@@ -1915,7 +1912,7 @@ public void stopChat_Should_ReturnInternalServerError_When_CallingConsultantDoes
   }
 
   @Test
-  public void stopChat_Should_ReturnBadRequest_When_ChatNotFound() throws Exception {
+  void stopChat_Should_ReturnBadRequest_When_ChatNotFound() throws Exception {
 
     when(accountProvider.retrieveValidatedConsultant()).thenReturn(TEAM_CONSULTANT);
     when(chatService.getChat(Mockito.anyLong())).thenReturn(Optional.empty());
@@ -1925,7 +1922,7 @@ public void stopChat_Should_ReturnBadRequest_When_ChatNotFound() throws Exceptio
   }
 
   @Test
-  public void stopChat_Should_ReturnOk_When_ChatWasStopped() throws Exception {
+  void stopChat_Should_ReturnOk_When_ChatWasStopped() throws Exception {
 
     when(accountProvider.retrieveValidatedConsultant()).thenReturn(TEAM_CONSULTANT);
     when(chatService.getChat(Mockito.anyLong())).thenReturn(Optional.of(chat));
@@ -1936,7 +1933,7 @@ public void stopChat_Should_ReturnOk_When_ChatWasStopped() throws Exception {
 
   /** Method: getChat */
   @Test
-  public void getChatMembers_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
+  void getChatMembers_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
 
     mvc.perform(
             get(PATH_GET_CHAT_MEMBERS_WITH_INVALID_PATH_PARAMS)
@@ -1953,7 +1950,7 @@ public void getChatMembers_Should_ReturnBadRequest_WhenPathParamsAreInvalid() th
   }
 
   @Test
-  public void getChatMembers_Should_ReturnOk_When_RequestOk() throws Exception {
+  void getChatMembers_Should_ReturnOk_When_RequestOk() throws Exception {
 
     mvc.perform(
             get(PATH_GET_CHAT_MEMBERS)
@@ -1966,7 +1963,7 @@ public void getChatMembers_Should_ReturnOk_When_RequestOk() throws Exception {
 
   /** Method: updateChat */
   @Test
-  public void updateChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
+  void updateChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws Exception {
 
     mvc.perform(
             put(PATH_PUT_UPDATE_CHAT_INVALID_PATH_PARAMS)
@@ -1978,7 +1975,7 @@ public void updateChat_Should_ReturnBadRequest_WhenPathParamsAreInvalid() throws
   }
 
   @Test
-  public void updateChat_Should_ReturnOk_When_RequestOk() throws Exception {
+  void updateChat_Should_ReturnOk_When_RequestOk() throws Exception {
 
     mvc.perform(
             put(PATH_PUT_UPDATE_CHAT)
@@ -1992,7 +1989,7 @@ public void updateChat_Should_ReturnOk_When_RequestOk() throws Exception {
 
   /** Method: fetchSessionForConsultant */
   @Test
-  public void fetchSessionForConsultant_Should_ReturnOk_WhenRequestOk() throws Exception {
+  void fetchSessionForConsultant_Should_ReturnOk_WhenRequestOk() throws Exception {
 
     mvc.perform(
             get(PATH_GET_SESSION_FOR_CONSULTANT)
@@ -2005,7 +2002,7 @@ public void fetchSessionForConsultant_Should_ReturnOk_WhenRequestOk() throws Exc
   }
 
   @Test
-  public void
+  void
       fetchSessionForConsultant_Should_ReturnInternalServerError_WhenAuthorizedButUserNotFound()
           throws Exception {
 
@@ -2024,7 +2021,7 @@ public void fetchSessionForConsultant_Should_ReturnOk_WhenRequestOk() throws Exc
   }
 
   @Test
-  public void updateEmailAddress_Should_ReturnOk_When_RequestOk() throws Exception {
+  void updateEmailAddress_Should_ReturnOk_When_RequestOk() throws Exception {
     mvc.perform(
             put(PATH_PUT_UPDATE_EMAIL)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -2036,7 +2033,7 @@ public void updateEmailAddress_Should_ReturnOk_When_RequestOk() throws Exception
   }
 
   @Test
-  public void deleteEmailAddress_Should_ReturnOk_When_RequestOk() throws Exception {
+  void deleteEmailAddress_Should_ReturnOk_When_RequestOk() throws Exception {
     mvc.perform(delete("/users/email").accept(MediaType.APPLICATION_JSON))
         .andExpect(status().isOk());
 
@@ -2044,7 +2041,7 @@ public void deleteEmailAddress_Should_ReturnOk_When_RequestOk() throws Exception
   }
 
   @Test
-  public void updateEmailAddress_Should_ReturnBadRequest_When_bodyIsEmpty() throws Exception {
+  void updateEmailAddress_Should_ReturnBadRequest_When_bodyIsEmpty() throws Exception {
     mvc.perform(
             put(PATH_PUT_UPDATE_EMAIL)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -2055,7 +2052,7 @@ public void updateEmailAddress_Should_ReturnBadRequest_When_bodyIsEmpty() throws
   }
 
   @Test
-  public void
+  void
       deactivateAndFlagUserAccountForDeletion_Should_ReturnBadRequest_When_BodyValuesAreMissing()
           throws Exception {
 
@@ -2069,7 +2066,7 @@ public void updateEmailAddress_Should_ReturnBadRequest_When_bodyIsEmpty() throws
   }
 
   @Test
-  public void deleteSessionAndInactiveUser_Should_ReturnNotFound_When_SessionIdIsUnknown()
+  void deleteSessionAndInactiveUser_Should_ReturnNotFound_When_SessionIdIsUnknown()
       throws Exception {
     var sessionId = easyRandom.nextLong();
 
@@ -2081,7 +2078,7 @@ public void deleteSessionAndInactiveUser_Should_ReturnNotFound_When_SessionIdIsU
   }
 
   @Test
-  public void deleteSessionAndInactiveUser_Should_ReturnOK_When_SessionIdIsKnown()
+  void deleteSessionAndInactiveUser_Should_ReturnOK_When_SessionIdIsKnown()
       throws Exception {
     var sessionId = givenAPresentSession(false);
 
@@ -2092,7 +2089,7 @@ public void deleteSessionAndInactiveUser_Should_ReturnOK_When_SessionIdIsKnown()
   }
 
   @Test
-  public void updateMobileToken_Should_ReturnOk_When_RequestOk() throws Exception {
+  void updateMobileToken_Should_ReturnOk_When_RequestOk() throws Exception {
     mvc.perform(
             put(PATH_PUT_UPDATE_MOBILE_TOKEN)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -2104,7 +2101,7 @@ public void updateMobileToken_Should_ReturnOk_When_RequestOk() throws Exception
   }
 
   @Test
-  public void updateMobileToken_Should_ReturnBadRequest_When_bodyIsEmpty() throws Exception {
+  void updateMobileToken_Should_ReturnBadRequest_When_bodyIsEmpty() throws Exception {
     mvc.perform(
             put(PATH_PUT_UPDATE_MOBILE_TOKEN)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -2115,7 +2112,7 @@ public void updateMobileToken_Should_ReturnBadRequest_When_bodyIsEmpty() throws
   }
 
   @Test
-  public void updateSessionData_Should_ReturnBadRequest_When_BodyIsEmpty() throws Exception {
+  void updateSessionData_Should_ReturnBadRequest_When_BodyIsEmpty() throws Exception {
     mvc.perform(
             put(PATH_PUT_UPDATE_SESSION_DATA)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -2126,7 +2123,7 @@ public void updateSessionData_Should_ReturnBadRequest_When_BodyIsEmpty() throws
   }
 
   @Test
-  public void updateSessionData_Should_ReturnBadRequest_When_PathVariableIsInvalid()
+  void updateSessionData_Should_ReturnBadRequest_When_PathVariableIsInvalid()
       throws Exception {
     mvc.perform(
             put(PATH_PUT_UPDATE_SESSION_DATA_INVALID_PATH_VAR)
@@ -2138,7 +2135,7 @@ public void updateSessionData_Should_ReturnBadRequest_When_PathVariableIsInvalid
   }
 
   @Test
-  public void updateSessionData_Should_ReturnOk_When_RequestIsOk() throws Exception {
+  void updateSessionData_Should_ReturnOk_When_RequestIsOk() throws Exception {
     mvc.perform(
             put(PATH_PUT_UPDATE_SESSION_DATA)
                 .content(objectMapper.writeValueAsString(new SessionDTO()))
@@ -2148,7 +2145,7 @@ public void updateSessionData_Should_ReturnOk_When_RequestIsOk() throws Exceptio
   }
 
   @Test
-  public void updateUserData_Should_ReturnNotFound_When_ConsultantDoesNotExist() throws Exception {
+  void updateUserData_Should_ReturnNotFound_When_ConsultantDoesNotExist() throws Exception {
     when(consultantService.getConsultant(anyString())).thenReturn(Optional.empty());
     var updateConsultant =
         objectMapper.writeValueAsString(givenAMinimalUpdateConsultantDto(givenAValidEmail()));
@@ -2164,7 +2161,7 @@ public void updateUserData_Should_ReturnNotFound_When_ConsultantDoesNotExist() t
   }
 
   @Test
-  public void updateUserData_Should_ReturnBadRequest_When_PathVariableIsInvalid() throws Exception {
+  void updateUserData_Should_ReturnBadRequest_When_PathVariableIsInvalid() throws Exception {
     mvc.perform(
             put(PATH_GET_USER_DATA)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -2175,7 +2172,7 @@ public void updateUserData_Should_ReturnBadRequest_When_PathVariableIsInvalid()
   }
 
   @Test
-  public void updateUserData_Should_ReturnBadRequest_When_LanguageIsInvalid() throws Exception {
+  void updateUserData_Should_ReturnBadRequest_When_LanguageIsInvalid() throws Exception {
     var updateConsultantDTO = givenAnUpdateConsultantDtoWithInvalidLanguage();
 
     mvc.perform(
@@ -2189,7 +2186,7 @@ public void updateUserData_Should_ReturnBadRequest_When_LanguageIsInvalid() thro
   }
 
   @Test
-  public void updateUserData_Should_ReturnOk_When_RequestIsOk() throws Exception {
+  void updateUserData_Should_ReturnOk_When_RequestIsOk() throws Exception {
     var consultant = givenAValidConsultant();
     var updateConsultantDTO = givenAMinimalUpdateConsultantDto(consultant.getEmail());
 
@@ -2213,7 +2210,7 @@ public void updateUserData_Should_ReturnOk_When_RequestIsOk() throws Exception {
   }
 
   @Test
-  public void updateUserData_Should_ReturnBadRequest_When_emailAddressIsNotValid()
+  void updateUserData_Should_ReturnBadRequest_When_emailAddressIsNotValid()
       throws Exception {
     var updateConsultantDto = givenAMinimalUpdateConsultantDto("invalid");
 
@@ -2226,7 +2223,7 @@ public void updateUserData_Should_ReturnBadRequest_When_emailAddressIsNotValid()
   }
 
   @Test
-  public void archiveSession_Should_ReturnBadRequest_When_PathVariableIsInvalid() throws Exception {
+  void archiveSession_Should_ReturnBadRequest_When_PathVariableIsInvalid() throws Exception {
     mvc.perform(
             put(PATH_ARCHIVE_SESSION_INVALID_PATH_VAR)
                 .contentType(MediaType.APPLICATION_JSON)
@@ -2237,12 +2234,12 @@ public void archiveSession_Should_ReturnBadRequest_When_PathVariableIsInvalid()
   }
 
   @Test
-  public void archiveSession_Should_ReturnOk_When_RequestIsOk() throws Exception {
+  void archiveSession_Should_ReturnOk_When_RequestIsOk() throws Exception {
     mvc.perform(put(PATH_ARCHIVE_SESSION)).andExpect(status().isOk());
   }
 
   @Test
-  public void dearchiveSession_Should_ReturnBadRequest_When_PathVariableIsInvalid()
+  void dearchiveSession_Should_ReturnBadRequest_When_PathVariableIsInvalid()
       throws Exception {
     mvc.perform(
             put(PATH_DEARCHIVE_SESSION_INVALID_PATH_VAR)
@@ -2254,12 +2251,12 @@ public void dearchiveSession_Should_ReturnBadRequest_When_PathVariableIsInvalid(
   }
 
   @Test
-  public void dearchiveSession_Should_ReturnOk_When_RequestIsOk() throws Exception {
+  void dearchiveSession_Should_ReturnOk_When_RequestIsOk() throws Exception {
     mvc.perform(put(PATH_DEARCHIVE_SESSION)).andExpect(status().isOk());
   }
 
   @Test
-  public void addMobileAppToken_Should_returnOk_When_RequestIsOk() throws Exception {
+  void addMobileAppToken_Should_returnOk_When_RequestIsOk() throws Exception {
     mvc.perform(
             put(PATH_PUT_ADD_MOBILE_TOKEN)
                 .content(objectMapper.writeValueAsString(new MobileTokenDTO()))
@@ -2268,13 +2265,13 @@ public void addMobileAppToken_Should_returnOk_When_RequestIsOk() throws Exceptio
   }
 
   @Test
-  public void addMobileAppToken_Should_returnBadRequest_When_RequestIsEmpty() throws Exception {
+  void addMobileAppToken_Should_returnBadRequest_When_RequestIsEmpty() throws Exception {
     mvc.perform(put(PATH_PUT_ADD_MOBILE_TOKEN).contentType(MediaType.APPLICATION_JSON))
         .andExpect(status().isBadRequest());
   }
 
   @Test
-  public void getConsultantPublicData_Should_returnOk_When_consultantIdIsGiven() throws Exception {
+  void getConsultantPublicData_Should_returnOk_When_consultantIdIsGiven() throws Exception {
     givenAValidConsultant();
 
     mvc.perform(get(PATH_GET_PUBLIC_CONSULTANT_DATA).contentType(MediaType.APPLICATION_JSON))
@@ -2285,7 +2282,7 @@ public void getConsultantPublicData_Should_returnOk_When_consultantIdIsGiven() t
   }
 
   @Test
-  public void
+  void
       updateE2eInChats_Should_returnAccepted_When_adviceSeekerWithoutInitializedSessionIsGiven()
           throws Exception {
     givenAdviceSeekerWithoutInitializedSession(false);
@@ -2303,7 +2300,7 @@ public void getConsultantPublicData_Should_returnOk_When_consultantIdIsGiven() t
   }
 
   @Test
-  public void
+  void
       updateE2eInChats_Should_returnServerError_When_adviceSeekerWithoutInitializedSessionShouldHaveBeenInitialized()
           throws Exception {
     givenAdviceSeekerWithoutInitializedSession(true);
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/interceptor/StatelessCsrfFilterTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/interceptor/StatelessCsrfFilterTest.java
index 6f4eeb245..f6a4cb782 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/interceptor/StatelessCsrfFilterTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/controller/interceptor/StatelessCsrfFilterTest.java
@@ -16,14 +16,16 @@
 import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
 import org.springframework.security.web.access.AccessDeniedHandler;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = org.mockito.quality.Strictness.LENIENT)
 public class StatelessCsrfFilterTest {
 
   private static final String CSRF_HEADER = "csrfHeader";
@@ -43,7 +45,7 @@ public class StatelessCsrfFilterTest {
 
   @Mock private AccessDeniedHandler accessDeniedHandler;
 
-  @Before
+  @BeforeEach
   public void setup() {
     ConfigProperty cookieProperty = new ConfigProperty();
     cookieProperty.setProperty(CSRF_COOKIE);
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/DecodeUsernameJsonSerializerTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/DecodeUsernameJsonSerializerTest.java
index 48a84bc80..baf96ad0f 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/DecodeUsernameJsonSerializerTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/DecodeUsernameJsonSerializerTest.java
@@ -8,13 +8,13 @@
 import com.fasterxml.jackson.core.JsonGenerator;
 import de.caritas.cob.userservice.api.helper.UserHelper;
 import java.io.IOException;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DecodeUsernameJsonSerializerTest {
 
   @InjectMocks private DecodeUsernameJsonSerializer serializer;
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/EncodeUsernameJsonSerializationUtilsTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/EncodeUsernameJsonSerializationUtilsTest.java
index 7ad61f61d..5da19e54a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/EncodeUsernameJsonSerializationUtilsTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/EncodeUsernameJsonSerializationUtilsTest.java
@@ -4,9 +4,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERNAME_ENCODED;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERNAME_TOO_LONG;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERNAME_TOO_SHORT;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.when;
 
@@ -19,14 +17,14 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class EncodeUsernameJsonSerializationUtilsTest {
 
   private ObjectMapper objectMapper;
@@ -35,7 +33,7 @@ public class EncodeUsernameJsonSerializationUtilsTest {
 
   @Mock private UserHelper userHelper;
 
-  @Before
+  @BeforeEach
   public void setup() {
     objectMapper = new ObjectMapper();
   }
@@ -68,7 +66,7 @@ public void deserialize_Should_ThrowBadRequestException_WhenUsernameIsTooShort()
 
       fail("Expected exception: BadRequestException");
     } catch (BadRequestException badRequestException) {
-      assertTrue("Excepted BadRequestException thrown", true);
+      assertTrue(true, "Excepted BadRequestException thrown");
     }
   }
 
@@ -82,7 +80,7 @@ public void deserialize_Should_ThrowBadRequestException_WhenUsernameIsTooLong()
 
       fail("Expected exception: BadRequestException");
     } catch (BadRequestException badRequestException) {
-      assertTrue("Excepted BadRequestException thrown", true);
+      assertTrue(true, "Excepted BadRequestException thrown");
     }
   }
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/UrlDecodePasswordJsonSerializationUtilsTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/UrlDecodePasswordJsonSerializationUtilsTest.java
index d058abf09..4b55c1230 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/UrlDecodePasswordJsonSerializationUtilsTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/serialization/UrlDecodePasswordJsonSerializationUtilsTest.java
@@ -2,7 +2,7 @@
 
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.PASSWORD;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.PASSWORD_URL_ENCODED;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import com.fasterxml.jackson.core.JsonParseException;
 import com.fasterxml.jackson.core.JsonParser;
@@ -12,18 +12,18 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class UrlDecodePasswordJsonSerializationUtilsTest {
 
   private ObjectMapper objectMapper;
   private UrlDecodePasswordJsonDeserializer urlDecodePasswordJsonDeserializer;
 
-  @Before
+  @BeforeEach
   public void setup() {
     objectMapper = new ObjectMapper();
     urlDecodePasswordJsonDeserializer = new UrlDecodePasswordJsonDeserializer();
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/MandatoryFieldsProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/MandatoryFieldsProviderTest.java
index 1a72a471c..624a38824 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/MandatoryFieldsProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/MandatoryFieldsProviderTest.java
@@ -4,20 +4,21 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTING_TYPE_SETTINGS_U25;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTING_TYPE_SETTINGS_WITHOUT_REGISTRATION;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTING_TYPE_SETTINGS_WITH_MANDATORY_FIELDS_NULL;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.exception.httpresponses.InternalServerErrorException;
 import de.caritas.cob.userservice.api.manager.consultingtype.ConsultingTypeManager;
 import de.caritas.cob.userservice.api.manager.consultingtype.registration.mandatoryfields.MandatoryFields;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class MandatoryFieldsProviderTest {
 
   @InjectMocks private MandatoryFieldsProvider mandatoryFieldsProvider;
@@ -40,23 +41,31 @@ public class MandatoryFieldsProviderTest {
         result.isState());
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       fetchMandatoryFieldsForConsultingType_Should_ThrowInternalServerError_WhenRegistrationIsNull() {
-    when(consultingTypeManager.getConsultingTypeSettings(Mockito.any()))
-        .thenReturn(CONSULTING_TYPE_SETTINGS_WITHOUT_REGISTRATION);
-    MandatoryFields result =
-        mandatoryFieldsProvider.fetchMandatoryFieldsForConsultingType(
-            Integer.toString(CONSULTING_TYPE_ID_U25));
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultingTypeManager.getConsultingTypeSettings(Mockito.any()))
+              .thenReturn(CONSULTING_TYPE_SETTINGS_WITHOUT_REGISTRATION);
+          MandatoryFields result =
+              mandatoryFieldsProvider.fetchMandatoryFieldsForConsultingType(
+                  Integer.toString(CONSULTING_TYPE_ID_U25));
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       fetchMandatoryFieldsForConsultingType_Should_ThrowInternalServerError_WhenMandatoryFieldsIsNull() {
-    when(consultingTypeManager.getConsultingTypeSettings(Mockito.any()))
-        .thenReturn(CONSULTING_TYPE_SETTINGS_WITH_MANDATORY_FIELDS_NULL);
-    MandatoryFields result =
-        mandatoryFieldsProvider.fetchMandatoryFieldsForConsultingType(
-            Integer.toString(CONSULTING_TYPE_ID_U25));
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultingTypeManager.getConsultingTypeSettings(Mockito.any()))
+              .thenReturn(CONSULTING_TYPE_SETTINGS_WITH_MANDATORY_FIELDS_NULL);
+          MandatoryFields result =
+              mandatoryFieldsProvider.fetchMandatoryFieldsForConsultingType(
+                  Integer.toString(CONSULTING_TYPE_ID_U25));
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/ValidAgeValidatorTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/ValidAgeValidatorTest.java
index 8db1888e7..a78d1f8ca 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/ValidAgeValidatorTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/ValidAgeValidatorTest.java
@@ -8,18 +8,18 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_DTO_WITHOUT_MANDATORY_AGE;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_DTO_WITH_AGE;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_DTO_WITH_INVALID_AGE;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.manager.consultingtype.registration.mandatoryfields.MandatoryFields;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ValidAgeValidatorTest {
 
   @InjectMocks private ValidAgeValidator validAgeValidator;
diff --git a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/ValidStateValidatorTest.java b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/ValidStateValidatorTest.java
index bf657546c..543436c64 100644
--- a/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/ValidStateValidatorTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/adapters/web/dto/validation/ValidStateValidatorTest.java
@@ -8,18 +8,18 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_DTO_WITHOUT_MANDATORY_STATE;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_DTO_WITH_INVALID_STATE;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_DTO_WITH_STATE;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.manager.consultingtype.registration.mandatoryfields.MandatoryFields;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ValidStateValidatorTest {
 
   @InjectMocks private ValidStateValidator validStateValidator;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/facade/AskerUserAdminFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/facade/AskerUserAdminFacadeTest.java
index 52cb0439a..7663e7b3d 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/facade/AskerUserAdminFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/facade/AskerUserAdminFacadeTest.java
@@ -3,6 +3,7 @@
 import static de.caritas.cob.userservice.api.helper.CustomLocalDateTime.nowInUtc;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -15,14 +16,14 @@
 import de.caritas.cob.userservice.api.model.User;
 import de.caritas.cob.userservice.api.service.user.UserService;
 import java.util.Optional;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class AskerUserAdminFacadeTest {
 
   @InjectMocks private AskerUserAdminFacade askerUserAdminFacade;
@@ -33,21 +34,29 @@ public class AskerUserAdminFacadeTest {
 
   @Mock private UsernameTranscoder usernameTranscoder;
 
-  @Test(expected = NotFoundException.class)
+  @Test
   public void markAskerForDeletion_Should_throwNotFoundException_When_askerDoesNotExist() {
-    when(this.userService.getUser(any())).thenReturn(Optional.empty());
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          when(this.userService.getUser(any())).thenReturn(Optional.empty());
 
-    this.askerUserAdminFacade.markAskerForDeletion("user id");
+          this.askerUserAdminFacade.markAskerForDeletion("user id");
+        });
   }
 
-  @Test(expected = ConflictException.class)
+  @Test
   public void
       markAskerForDeletion_Should_throwConflictException_When_askerIsAlreadyMarkedForDeletion() {
-    User user = new User();
-    user.setDeleteDate(nowInUtc());
-    when(this.userService.getUser(any())).thenReturn(Optional.of(user));
+    assertThrows(
+        ConflictException.class,
+        () -> {
+          User user = new User();
+          user.setDeleteDate(nowInUtc());
+          when(this.userService.getUser(any())).thenReturn(Optional.of(user));
 
-    this.askerUserAdminFacade.markAskerForDeletion("user id");
+          this.askerUserAdminFacade.markAskerForDeletion("user id");
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/facade/ConsultantAdminFacadeIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/facade/ConsultantAdminFacadeIT.java
index 8d52784c7..919f26054 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/facade/ConsultantAdminFacadeIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/facade/ConsultantAdminFacadeIT.java
@@ -36,8 +36,7 @@
 import org.jeasy.random.EasyRandom;
 import org.jeasy.random.EasyRandomParameters;
 import org.jeasy.random.FieldPredicates;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -46,9 +45,7 @@
 import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.annotation.DirtiesContext.ClassMode;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/model/AgencyDependedViolationReportRuleTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/model/AgencyDependedViolationReportRuleTest.java
index ea11671f6..c18aaac4a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/model/AgencyDependedViolationReportRuleTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/model/AgencyDependedViolationReportRuleTest.java
@@ -9,27 +9,27 @@
 import de.caritas.cob.userservice.agencyadminserivce.generated.web.model.AgencyAdminResponseDTO;
 import de.caritas.cob.userservice.api.adapters.web.dto.ViolationDTO;
 import java.util.List;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
-public class AgencyDependedViolationReportRuleTest {
+class AgencyDependedViolationReportRuleTest {
 
   private AgencyDependedViolationReportRule reportRule =
       new AgencyDependedViolationReportRule() {
         @Override
-        public List<ViolationDTO> generateViolations() {
+        List<ViolationDTO> generateViolations() {
           return emptyList();
         }
       };
 
   @Test
-  public void getAllAgencies_Should_returnEmptyList_When_noAgenciesHaveBeenSet() {
+  void getAllAgencies_Should_returnEmptyList_When_noAgenciesHaveBeenSet() {
     List<AgencyAdminResponseDTO> allAgencies = reportRule.getAllAgencies();
 
     assertThat(allAgencies, is(emptyList()));
   }
 
   @Test
-  public void getAllAgencies_Should_returnExpectedList_When_agenciesHaveBeenSet() {
+  void getAllAgencies_Should_returnExpectedList_When_agenciesHaveBeenSet() {
     List<AgencyAdminResponseDTO> agencies =
         asList(new AgencyAdminResponseDTO(), new AgencyAdminResponseDTO());
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/registry/ViolationRuleRegistryTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/registry/ViolationRuleRegistryTest.java
index 93f2e1f93..0affe677f 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/registry/ViolationRuleRegistryTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/registry/ViolationRuleRegistryTest.java
@@ -15,16 +15,18 @@
 import de.caritas.cob.userservice.api.admin.report.model.ViolationReportRule;
 import java.util.List;
 import java.util.Map;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
 import org.springframework.context.ApplicationContext;
 
-@RunWith(MockitoJUnitRunner.class)
-public class ViolationRuleRegistryTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = org.mockito.quality.Strictness.LENIENT)
+class ViolationRuleRegistryTest {
 
   @InjectMocks private ViolationRuleRegistry violationRuleRegistry;
 
@@ -32,8 +34,8 @@ public class ViolationRuleRegistryTest {
 
   @Mock private AgencyDependedViolationReportRule agencyDependedViolationReportRule;
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void setup() {
     Map<String, ViolationReportRule> mockedBeans = mock(Map.class);
     List<ViolationReportRule> mockedRules =
         asList(mock(ViolationReportRule.class), agencyDependedViolationReportRule);
@@ -42,7 +44,7 @@ public void setup() {
   }
 
   @Test
-  public void getViolationReportRules_Should_returnRegistratedRules_When_regitryIsInitialized() {
+  void getViolationReportRules_Should_returnRegistratedRules_When_regitryIsInitialized() {
     this.violationRuleRegistry.initialize();
 
     List<ViolationReportRule> registeredRules =
@@ -53,7 +55,7 @@ public void getViolationReportRules_Should_returnRegistratedRules_When_regitryIs
   }
 
   @Test
-  public void getViolationReportRules_Should_returnEmptyList_When_regitryIsNotInitialized() {
+  void getViolationReportRules_Should_returnEmptyList_When_regitryIsNotInitialized() {
     List<ViolationReportRule> registeredRules =
         this.violationRuleRegistry.getViolationReportRules(emptyList());
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/ConsultantWithWrongTeamConsultantFlagViolationReportRuleTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/ConsultantWithWrongTeamConsultantFlagViolationReportRuleTest.java
index 11196cfa9..8c31482c5 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/ConsultantWithWrongTeamConsultantFlagViolationReportRuleTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/ConsultantWithWrongTeamConsultantFlagViolationReportRuleTest.java
@@ -17,13 +17,13 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantWithWrongTeamConsultantFlagViolationReportRuleTest {
 
   @InjectMocks private ConsultantWithWrongTeamConsultantFlagViolationReportRule reportRule;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/InvalidAgencyForConsultantViolationReportRuleTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/InvalidAgencyForConsultantViolationReportRuleTest.java
index 20b200e3b..f443f7df7 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/InvalidAgencyForConsultantViolationReportRuleTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/InvalidAgencyForConsultantViolationReportRuleTest.java
@@ -16,13 +16,13 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class InvalidAgencyForConsultantViolationReportRuleTest {
 
   @InjectMocks private InvalidAgencyForConsultantViolationReportRule reportRule;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingAgencyForConsultantViolationReportRuleTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingAgencyForConsultantViolationReportRuleTest.java
index 378526f0b..cfeb4b0fd 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingAgencyForConsultantViolationReportRuleTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingAgencyForConsultantViolationReportRuleTest.java
@@ -13,13 +13,13 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class MissingAgencyForConsultantViolationReportRuleTest {
 
   @InjectMocks private MissingAgencyForConsultantViolationReportRule reportRule;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingRocketChatRoomForConsultantViolationReportRuleTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingRocketChatRoomForConsultantViolationReportRuleTest.java
index a42fbfabb..ec46a85c9 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingRocketChatRoomForConsultantViolationReportRuleTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingRocketChatRoomForConsultantViolationReportRuleTest.java
@@ -23,13 +23,13 @@
 import de.caritas.cob.userservice.api.service.LogService;
 import java.util.List;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class MissingRocketChatRoomForConsultantViolationReportRuleTest {
 
   @InjectMocks private MissingRocketChatRoomForConsultantViolationReportRule reportRule;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingSessionAndChatForAskerViolationReportRuleTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingSessionAndChatForAskerViolationReportRuleTest.java
index baa9e853b..95f2bb9bd 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingSessionAndChatForAskerViolationReportRuleTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/MissingSessionAndChatForAskerViolationReportRuleTest.java
@@ -14,13 +14,13 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class MissingSessionAndChatForAskerViolationReportRuleTest {
 
   @InjectMocks private MissingSessionAndChatForAskerViolationReportRule reportRule;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/TeamConsultantWithoutRequiredFlagViolationReportRuleTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/TeamConsultantWithoutRequiredFlagViolationReportRuleTest.java
index adc6c4d33..b82474d8c 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/TeamConsultantWithoutRequiredFlagViolationReportRuleTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/rule/TeamConsultantWithoutRequiredFlagViolationReportRuleTest.java
@@ -16,13 +16,13 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class TeamConsultantWithoutRequiredFlagViolationReportRuleTest {
 
   @InjectMocks private TeamConsultantWithoutRequiredFlagViolationReportRule reportRule;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/service/AgencyAdminServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/service/AgencyAdminServiceTest.java
index d63808834..ede8cee00 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/service/AgencyAdminServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/service/AgencyAdminServiceTest.java
@@ -1,6 +1,6 @@
 package de.caritas.cob.userservice.api.admin.report.service;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.agencyadminserivce.generated.ApiClient;
@@ -9,17 +9,17 @@
 import de.caritas.cob.userservice.api.config.apiclient.AgencyAdminServiceApiControllerFactory;
 import de.caritas.cob.userservice.api.service.httpheader.SecurityHeaderSupplier;
 import de.caritas.cob.userservice.api.service.httpheader.TenantHeaderSupplier;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.http.HttpHeaders;
 import org.springframework.test.util.ReflectionTestUtils;
 import org.springframework.web.client.RestTemplate;
 
-@RunWith(MockitoJUnitRunner.class)
-public class AgencyAdminServiceTest {
+@ExtendWith(MockitoExtension.class)
+class AgencyAdminServiceTest {
 
   @InjectMocks private AgencyAdminService agencyAdminService;
   @Mock private SecurityHeaderSupplier securityHeaderSupplier;
@@ -31,7 +31,7 @@ public class AgencyAdminServiceTest {
   @Mock private AgencyAdminServiceApiControllerFactory agencyAdminServiceApiControllerFactory;
 
   @Test
-  public void agencyAdminControllerShouldHaveCorrectHeaders() {
+  void agencyAdminControllerShouldHaveCorrectHeaders() {
     var headers = new HttpHeaders();
     headers.add("header1", "header1");
     when(securityHeaderSupplier.getKeycloakAndCsrfHttpHeaders()).thenReturn(headers);
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/report/service/ViolationReportGeneratorTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/report/service/ViolationReportGeneratorTest.java
index 8c4d63862..a989aea1f 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/report/service/ViolationReportGeneratorTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/report/service/ViolationReportGeneratorTest.java
@@ -14,14 +14,14 @@
 import java.io.IOException;
 import java.util.List;
 import org.apache.commons.io.FileUtils;
-import org.junit.After;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ViolationReportGeneratorTest {
 
   @InjectMocks private ViolationReportGenerator violationReportGenerator;
@@ -30,7 +30,7 @@ public class ViolationReportGeneratorTest {
 
   @Mock private AgencyAdminService agencyAdminService;
 
-  @After
+  @AfterEach
   public void cleanGeneratedFiles() throws IOException {
     FileUtils.deleteDirectory(new File("report"));
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/create/CreateAdminServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/create/CreateAdminServiceIT.java
index a115750f2..68de3efbe 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/create/CreateAdminServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/create/CreateAdminServiceIT.java
@@ -5,10 +5,7 @@
 import static de.caritas.cob.userservice.api.config.auth.UserRole.USER_ADMIN;
 import static de.caritas.cob.userservice.api.exception.httpresponses.customheader.HttpStatusExceptionReason.EMAIL_NOT_VALID;
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
@@ -27,9 +24,8 @@
 import de.caritas.cob.userservice.api.tenant.TenantContext;
 import java.util.List;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
 import org.junit.jupiter.api.AfterEach;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Captor;
 import org.powermock.reflect.Whitebox;
@@ -39,14 +35,12 @@
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.util.ReflectionTestUtils;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
-public class CreateAdminServiceIT {
+class CreateAdminServiceIT {
 
   private static final String VALID_USERNAME = "validUsername";
   private static final String VALID_EMAIL_ADDRESS = "valid@emailaddress.de";
@@ -57,14 +51,15 @@ public class CreateAdminServiceIT {
   private final EasyRandom easyRandom = new EasyRandom();
 
   @AfterEach
-  public void afterTests() {
+  void afterTests() {
     TenantContext.clear();
   }
 
   @Test
-  public void
+  void
       createNewAdminAgency_Should_returnExpectedCreatedAdmin_When_inputDataIsCorrectAndMultitenancyDisabled() {
     // given
+    TenantContext.setCurrentTenant(1L);
     ReflectionTestUtils.setField(createAdminService, "multiTenancyEnabled", false);
     when(identityClient.createKeycloakUser(any(), anyString(), any()))
         .thenReturn(easyRandom.nextObject(KeycloakCreateUserResponseDTO.class));
@@ -97,7 +92,7 @@ public void afterTests() {
   }
 
   @Test
-  public void
+  void
       createNewAdminAgency_Should_returnExpectedCreatedAdmin_When_inputDataIsCorrectAndMultitenancyEnabled() {
     // given
     ReflectionTestUtils.setField(createAdminService, "multiTenancyEnabled", true);
@@ -134,7 +129,7 @@ public void afterTests() {
   }
 
   @Test
-  public void getUserRolesForTenantAdmin_ShouldGetProperDefaultRoles_ForSingleDomainMultitenancy() {
+  void getUserRolesForTenantAdmin_ShouldGetProperDefaultRoles_ForSingleDomainMultitenancy() {
     Whitebox.setInternalState(createAdminService, "multitenancyWithSingleDomain", true);
     List<UserRole> defaultRoles = this.createAdminService.getDefaultRoles(AdminType.TENANT);
 
@@ -143,7 +138,7 @@ public void getUserRolesForTenantAdmin_ShouldGetProperDefaultRoles_ForSingleDoma
   }
 
   @Test
-  public void getUserRolesForTenantAdmin_ShouldGetProperDefaultRoles_ForMultidomainMultitenancy() {
+  void getUserRolesForTenantAdmin_ShouldGetProperDefaultRoles_ForMultidomainMultitenancy() {
     Whitebox.setInternalState(createAdminService, "multitenancyWithSingleDomain", false);
     List<UserRole> defaultRoles = this.createAdminService.getDefaultRoles(AdminType.TENANT);
 
@@ -151,25 +146,32 @@ public void getUserRolesForTenantAdmin_ShouldGetProperDefaultRoles_ForMultidomai
         .containsOnly(UserRole.AGENCY_ADMIN, UserRole.SINGLE_TENANT_ADMIN, USER_ADMIN, TOPIC_ADMIN);
   }
 
-  @Test(expected = CustomValidationHttpStatusException.class)
-  public void
+  @Test
+  void
       createNewAdminAgency_Should_throwCustomValidationHttpStatusException_When_keycloakIdIsMissing() {
-    // given
-    KeycloakCreateUserResponseDTO keycloakResponse =
-        easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
-    keycloakResponse.setUserId(null);
-    when(identityClient.createKeycloakUser(any(), anyString(), any())).thenReturn(keycloakResponse);
-    CreateAdminDTO createAgencyAdminDTO = this.easyRandom.nextObject(CreateAdminDTO.class);
-
-    // when
-    this.createAdminService.createNewAgencyAdmin(createAgencyAdminDTO);
+    TenantContext.setCurrentTenant(1L);
+    assertThrows(
+        CustomValidationHttpStatusException.class,
+        () -> {
+          // given
+          KeycloakCreateUserResponseDTO keycloakResponse =
+              easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
+          keycloakResponse.setUserId(null);
+          when(identityClient.createKeycloakUser(any(), anyString(), any()))
+              .thenReturn(keycloakResponse);
+          CreateAdminDTO createAgencyAdminDTO = this.easyRandom.nextObject(CreateAdminDTO.class);
+
+          // when
+          this.createAdminService.createNewAgencyAdmin(createAgencyAdminDTO);
+        });
   }
 
   @Test
-  public void createNewAdminAgency_Should_throwExpectedException_When_emailIsInvalid() {
+  void createNewAdminAgency_Should_throwExpectedException_When_emailIsInvalid() {
     // given
     CreateAdminDTO createAgencyAdminDTO = this.easyRandom.nextObject(CreateAdminDTO.class);
     createAgencyAdminDTO.setEmail("invalid");
+    TenantContext.setCurrentTenant(1L);
 
     try {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/create/agencyrelation/CreateAdminAgencyRelationServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/create/agencyrelation/CreateAdminAgencyRelationServiceIT.java
index 7fe6fbc8b..53fba1be7 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/create/agencyrelation/CreateAdminAgencyRelationServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/create/agencyrelation/CreateAdminAgencyRelationServiceIT.java
@@ -3,6 +3,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.UserServiceApplication;
@@ -17,17 +18,14 @@
 import de.caritas.cob.userservice.api.service.agency.AgencyService;
 import java.util.List;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -62,27 +60,36 @@ public void create_Should_createExpectedCreatedAdmin_When_inputDataIsCorrect() {
     assertThat(result, hasSize(1));
   }
 
-  @Test(expected = NoContentException.class)
+  @Test
   public void create_Should_throwNoContentException_When_adminDoesNotExist() {
-    // given
-    CreateAdminAgencyRelationDTO createAdminAgencyRelationDTO =
-        easyRandom.nextObject(CreateAdminAgencyRelationDTO.class);
+    assertThrows(
+        NoContentException.class,
+        () -> {
+          // given
+          CreateAdminAgencyRelationDTO createAdminAgencyRelationDTO =
+              easyRandom.nextObject(CreateAdminAgencyRelationDTO.class);
 
-    // then
-    this.createAdminAgencyRelationService.create("invalid", createAdminAgencyRelationDTO);
+          // then
+          this.createAdminAgencyRelationService.create("invalid", createAdminAgencyRelationDTO);
+        });
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void create_Should_throwBadRequestException_When_agencyDoesNotExist() {
-    // given
-    CreateAdminAgencyRelationDTO createAdminAgencyRelationDTO = new CreateAdminAgencyRelationDTO();
-    long agencyId = 99L;
-    createAdminAgencyRelationDTO.setAgencyId(agencyId);
-    when(agencyService.getAgencyWithoutCaching(agencyId))
-        .thenThrow(new BadRequestException("Agency not found"));
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          // given
+          CreateAdminAgencyRelationDTO createAdminAgencyRelationDTO =
+              new CreateAdminAgencyRelationDTO();
+          long agencyId = 99L;
+          createAdminAgencyRelationDTO.setAgencyId(agencyId);
+          when(agencyService.getAgencyWithoutCaching(agencyId))
+              .thenThrow(new BadRequestException("Agency not found"));
 
-    // then
-    createAdminAgencyRelationService.create(VALID_ADMIN_ID, createAdminAgencyRelationDTO);
+          // then
+          createAdminAgencyRelationService.create(VALID_ADMIN_ID, createAdminAgencyRelationDTO);
+        });
   }
 
   private Admin createAdminWithoutAgency() {
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/delete/DeleteAdminServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/delete/DeleteAdminServiceTest.java
index 0b3531818..9548a46ca 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/delete/DeleteAdminServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/delete/DeleteAdminServiceTest.java
@@ -5,13 +5,13 @@
 import de.caritas.cob.userservice.api.port.out.AdminAgencyRepository;
 import de.caritas.cob.userservice.api.port.out.AdminRepository;
 import de.caritas.cob.userservice.api.port.out.IdentityClient;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteAdminServiceTest {
 
   private final String VALID_ADMIN_ID = "164be67d-4d1b-4d80-bb6b-0ee057a1c59e";
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/search/RetrieveAdminServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/search/RetrieveAdminServiceIT.java
index a1cd20c0e..fc0d07573 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/search/RetrieveAdminServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/search/RetrieveAdminServiceIT.java
@@ -5,6 +5,7 @@
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import de.caritas.cob.userservice.api.UserServiceApplication;
 import de.caritas.cob.userservice.api.exception.httpresponses.NoContentException;
@@ -14,8 +15,7 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -23,9 +23,7 @@
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageRequest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -46,11 +44,15 @@ public void findAgencyAdmin_Should_returnCorrectAdmin_When_correctIdIsProvided()
     assertThat(admin.getId(), is(VALID_ADMIN_ID));
   }
 
-  @Test(expected = NoContentException.class)
+  @Test
   public void findAgencyAdmin_Should_throwNoContentException_When_incorrectIdIsProvided() {
-    // given
-    // when
-    retrieveAdminService.findAdmin("invalid", Admin.AdminType.AGENCY);
+    assertThrows(
+        NoContentException.class,
+        () -> {
+          // given
+          // when
+          retrieveAdminService.findAdmin("invalid", Admin.AdminType.AGENCY);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/search/RetrieveAdminServiceTenantAwareIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/search/RetrieveAdminServiceTenantAwareIT.java
index 70885146d..8df5ed682 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/search/RetrieveAdminServiceTenantAwareIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/search/RetrieveAdminServiceTenantAwareIT.java
@@ -18,7 +18,6 @@
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.extension.ExtendWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -26,10 +25,8 @@
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageRequest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit.jupiter.SpringExtension;
 import org.springframework.transaction.annotation.Transactional;
 
-@ExtendWith(SpringExtension.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/update/UpdateAdminServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/update/UpdateAdminServiceIT.java
index 8af4d9cb4..be3a193d4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/update/UpdateAdminServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/update/UpdateAdminServiceIT.java
@@ -4,7 +4,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.fail;
 
 import de.caritas.cob.userservice.api.UserServiceApplication;
 import de.caritas.cob.userservice.api.adapters.web.dto.UpdateAgencyAdminDTO;
@@ -12,17 +12,14 @@
 import de.caritas.cob.userservice.api.exception.httpresponses.CustomValidationHttpStatusException;
 import de.caritas.cob.userservice.api.model.Admin;
 import de.caritas.cob.userservice.api.port.out.IdentityClient;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/update/agencyrelation/SynchronizeAdminAgencyRelationIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/update/agencyrelation/SynchronizeAdminAgencyRelationIT.java
index 8a7726581..32d361975 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/update/agencyrelation/SynchronizeAdminAgencyRelationIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/admin/update/agencyrelation/SynchronizeAdminAgencyRelationIT.java
@@ -19,8 +19,7 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -29,9 +28,7 @@
 import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.annotation.DirtiesContext.ClassMode;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceIT.java
index f0b82dd52..d6812b2c5 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceIT.java
@@ -10,8 +10,8 @@
 import static org.hamcrest.Matchers.lessThan;
 import static org.hamcrest.Matchers.not;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -30,17 +30,14 @@
 import java.util.Set;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceTenantAwareIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceTenantAwareIT.java
index f3d0df767..95b08dfc4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceTenantAwareIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceTenantAwareIT.java
@@ -9,7 +9,7 @@
 import static org.hamcrest.Matchers.lessThan;
 import static org.hamcrest.Matchers.not;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -33,20 +33,17 @@
 import java.util.List;
 import java.util.Set;
 import org.jeasy.random.EasyRandom;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.transaction.annotation.Transactional;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -77,12 +74,12 @@ public class ConsultantAgencyAdminUserServiceTenantAwareIT {
 
   private Set<String> consultantsToRemove = Sets.newHashSet();
 
-  @Before
+  @BeforeEach
   public void beforeTests() {
     TenantContext.setCurrentTenant(1L);
   }
 
-  @After
+  @AfterEach
   public void afterTests() {
     consultantsToRemove.stream().forEach(id -> consultantRepository.deleteById(id));
     TenantContext.clear();
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceTest.java
index 4d1515753..1af1811c9 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyAdminUserServiceTest.java
@@ -6,8 +6,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.Assert.fail;
-import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyList;
 import static org.mockito.Mockito.times;
@@ -28,13 +27,13 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantAgencyAdminUserServiceTest {
 
   @InjectMocks private ConsultantAgencyAdminService consultantAgencyAdminService;
@@ -116,21 +115,26 @@ public void removeConsultantsFromTeamSessionsByAgencyId_Should_changeTeamSession
     verify(this.consultantRepository, times(10)).save(any());
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       removeConsultantsFromTeamSessionsByAgencyId_Should_throwInternalServerErrorException_When_agencyServiceFails() {
-    Session session = new EasyRandom().nextObject(Session.class);
-    session.setTeamSession(true);
-    List<Consultant> consultants =
-        new EasyRandom().objects(Consultant.class, 10).collect(Collectors.toList());
-
-    when(this.sessionRepository.findByAgencyIdAndStatusAndTeamSessionIsTrue(any(), any()))
-        .thenReturn(singletonList(session));
-    when(this.consultantRepository.findByConsultantAgenciesAgencyIdInAndDeleteDateIsNull(anyList()))
-        .thenReturn(consultants);
-    when(this.agencyService.getAgency(any())).thenThrow(new InternalServerErrorException(""));
-
-    this.consultantAgencyAdminService.removeConsultantsFromTeamSessionsByAgencyId(1L);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          Session session = new EasyRandom().nextObject(Session.class);
+          session.setTeamSession(true);
+          List<Consultant> consultants =
+              new EasyRandom().objects(Consultant.class, 10).collect(Collectors.toList());
+
+          when(this.sessionRepository.findByAgencyIdAndStatusAndTeamSessionIsTrue(any(), any()))
+              .thenReturn(singletonList(session));
+          when(this.consultantRepository.findByConsultantAgenciesAgencyIdInAndDeleteDateIsNull(
+                  anyList()))
+              .thenReturn(consultants);
+          when(this.agencyService.getAgency(any())).thenThrow(new InternalServerErrorException(""));
+
+          this.consultantAgencyAdminService.removeConsultantsFromTeamSessionsByAgencyId(1L);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyDeletionValidationServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyDeletionValidationServiceTest.java
index 2b601ae55..cb98e9a7b 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyDeletionValidationServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/ConsultantAgencyDeletionValidationServiceTest.java
@@ -6,8 +6,7 @@
 import static java.util.Objects.requireNonNull;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.fail;
-import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
@@ -21,13 +20,13 @@
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
 import de.caritas.cob.userservice.api.service.agency.AgencyService;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantAgencyDeletionValidationServiceTest {
 
   @InjectMocks private ConsultantAgencyDeletionValidationService agencyDeletionValidationService;
@@ -80,17 +79,21 @@ public class ConsultantAgencyDeletionValidationServiceTest {
     }
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       validateForDeletion_Should_throwInternalServerErrorException_When_agencyCanNotBeFetched() {
-    ConsultantAgency consultantAgency = new EasyRandom().nextObject(ConsultantAgency.class);
-    consultantAgency.setDeleteDate(null);
-    when(this.consultantAgencyRepository.findByAgencyIdAndDeleteDateIsNull(any()))
-        .thenReturn(singletonList(consultantAgency));
-    when(this.agencyService.getAgencyWithoutCaching(any()))
-        .thenThrow(new InternalServerErrorException(""));
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          ConsultantAgency consultantAgency = new EasyRandom().nextObject(ConsultantAgency.class);
+          consultantAgency.setDeleteDate(null);
+          when(this.consultantAgencyRepository.findByAgencyIdAndDeleteDateIsNull(any()))
+              .thenReturn(singletonList(consultantAgency));
+          when(this.agencyService.getAgencyWithoutCaching(any()))
+              .thenThrow(new InternalServerErrorException(""));
 
-    this.agencyDeletionValidationService.validateAndMarkForDeletion(consultantAgency);
+          this.agencyDeletionValidationService.validateAndMarkForDeletion(consultantAgency);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/RemoveConsultantFromRocketChatServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/RemoveConsultantFromRocketChatServiceTest.java
index 25cc01674..d2c1b7472 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/RemoveConsultantFromRocketChatServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/agency/RemoveConsultantFromRocketChatServiceTest.java
@@ -15,13 +15,13 @@
 import de.caritas.cob.userservice.api.port.out.ConsultantRepository;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RemoveConsultantFromRocketChatServiceTest {
 
   @InjectMocks private RemoveConsultantFromRocketChatService removeConsultantFromRocketChatService;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminFilterServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminFilterServiceIT.java
index 2b93ab181..794e19fc3 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminFilterServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminFilterServiceIT.java
@@ -1,15 +1,12 @@
 package de.caritas.cob.userservice.api.admin.service.consultant;
 
 import de.caritas.cob.userservice.api.UserServiceApplication;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminFilterServiceTenantAwareIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminFilterServiceTenantAwareIT.java
index 1eeef5b1b..fc7eac760 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminFilterServiceTenantAwareIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminFilterServiceTenantAwareIT.java
@@ -3,19 +3,16 @@
 import de.caritas.cob.userservice.api.UserServiceApplication;
 import de.caritas.cob.userservice.api.port.out.ConsultantRepository;
 import de.caritas.cob.userservice.api.tenant.TenantContext;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.transaction.annotation.Transactional;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -28,12 +25,12 @@ public class ConsultantAdminFilterServiceTenantAwareIT extends ConsultantAdminFi
 
   @Autowired ConsultantRepository consultantRepository;
 
-  @Before
+  @BeforeEach
   public void beforeTests() {
     TenantContext.setCurrentTenant(1L);
   }
 
-  @After
+  @AfterEach
   public void afterTests() {
     TenantContext.clear();
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminServiceIT.java
index b11cfa990..63bcd3b88 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminServiceIT.java
@@ -4,6 +4,7 @@
 import static org.hamcrest.Matchers.endsWith;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -28,17 +29,14 @@
 import org.jeasy.random.EasyRandom;
 import org.jeasy.random.EasyRandomParameters;
 import org.jeasy.random.FieldPredicates;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -112,9 +110,13 @@ public void findConsultantById_Should_returnExpectedConsultantLinks_When_consult
     assertThat(consultantById.getLinks().getAddAgency().getMethod(), is(MethodEnum.POST));
   }
 
-  @Test(expected = NoContentException.class)
+  @Test
   public void findConsultantById_Should_throwNoContentException_When_consultantIdDoesNotExist() {
-    this.consultantAdminService.findConsultantById("Invalid");
+    assertThrows(
+        NoContentException.class,
+        () -> {
+          this.consultantAdminService.findConsultantById("Invalid");
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminServiceTest.java
index 1ac07aa16..c844bbc08 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/ConsultantAdminServiceTest.java
@@ -1,5 +1,6 @@
 package de.caritas.cob.userservice.api.admin.service.consultant;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
@@ -17,13 +18,13 @@
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
 import de.caritas.cob.userservice.api.service.appointment.AppointmentService;
 import java.util.Optional;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantAdminServiceTest {
 
   @InjectMocks private ConsultantAdminService consultantAdminService;
@@ -44,12 +45,17 @@ public class ConsultantAdminServiceTest {
 
   @Mock private AccountManager accountManager;
 
-  @Test(expected = NotFoundException.class)
+  @Test
   public void
       markConsultantForDeletion_Should_throwNotFoundException_When_consultantdoesNotExist() {
-    when(this.consultantRepository.findByIdAndDeleteDateIsNull(any())).thenReturn(Optional.empty());
-
-    this.consultantAdminService.markConsultantForDeletion("id", false);
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          when(this.consultantRepository.findByIdAndDeleteDateIsNull(any()))
+              .thenReturn(Optional.empty());
+
+          this.consultantAdminService.markConsultantForDeletion("id", false);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/CreateConsultantSagaIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/CreateConsultantSagaIT.java
index f2aaaa0c0..4dde4f659 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/CreateConsultantSagaIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/CreateConsultantSagaIT.java
@@ -7,7 +7,8 @@
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hibernate.validator.internal.util.CollectionHelper.asSet;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyBoolean;
 import static org.mockito.ArgumentMatchers.anyString;
@@ -40,9 +41,8 @@
 import de.caritas.cob.userservice.tenantadminservice.generated.web.model.Settings;
 import de.caritas.cob.userservice.tenantadminservice.generated.web.model.TenantDTO;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
@@ -50,10 +50,8 @@
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.util.ReflectionTestUtils;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -80,7 +78,7 @@ public class CreateConsultantSagaIT {
 
   private final EasyRandom easyRandom = new EasyRandom();
 
-  @Before
+  @BeforeEach
   public void setup() {
     ReflectionTestUtils.setField(createConsultantSaga, "appointmentFeatureEnabled", false);
   }
@@ -306,37 +304,47 @@ public void createNewConsultant_Should_callRollback_When_anyOfTheServicesThrowsE
     assertThat(consultant.getFullName(), notNullValue());
   }
 
-  @Test(expected = DistributedTransactionException.class)
+  @Test
   public void
       createNewConsultant_Should_throwCustomValidationHttpStatusException_When_userCanNotBeCreatedInRocketChat()
           throws RocketChatLoginException {
-    when(rocketChatService.getUserID(anyString(), anyString(), anyBoolean()))
-        .thenThrow(new RocketChatLoginException(""));
-    KeycloakCreateUserResponseDTO validKeycloakResponse =
-        easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
-    when(keycloakService.createKeycloakUser(any(), anyString(), any()))
-        .thenReturn(validKeycloakResponse);
-    CreateConsultantDTO createConsultantDTO = this.easyRandom.nextObject(CreateConsultantDTO.class);
-    createConsultantDTO.setUsername(VALID_USERNAME);
-    createConsultantDTO.setEmail(VALID_EMAILADDRESS);
-
-    this.createConsultantSaga.createNewConsultant(createConsultantDTO);
+    assertThrows(
+        DistributedTransactionException.class,
+        () -> {
+          when(rocketChatService.getUserID(anyString(), anyString(), anyBoolean()))
+              .thenThrow(new RocketChatLoginException(""));
+          KeycloakCreateUserResponseDTO validKeycloakResponse =
+              easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
+          when(keycloakService.createKeycloakUser(any(), anyString(), any()))
+              .thenReturn(validKeycloakResponse);
+          CreateConsultantDTO createConsultantDTO =
+              this.easyRandom.nextObject(CreateConsultantDTO.class);
+          createConsultantDTO.setUsername(VALID_USERNAME);
+          createConsultantDTO.setEmail(VALID_EMAILADDRESS);
+
+          this.createConsultantSaga.createNewConsultant(createConsultantDTO);
+        });
   }
 
-  @Test(expected = CustomValidationHttpStatusException.class)
+  @Test
   public void
       createNewConsultant_Should_throwCustomValidationHttpStatusException_When_keycloakIdIsMissing()
           throws RocketChatLoginException {
-    when(rocketChatService.getUserID(anyString(), anyString(), anyBoolean()))
-        .thenReturn(DUMMY_RC_ID);
-    KeycloakCreateUserResponseDTO keycloakResponse =
-        easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
-    keycloakResponse.setUserId(null);
-    when(keycloakService.createKeycloakUser(any(), anyString(), any()))
-        .thenReturn(keycloakResponse);
-    CreateConsultantDTO createConsultantDTO = this.easyRandom.nextObject(CreateConsultantDTO.class);
-
-    this.createConsultantSaga.createNewConsultant(createConsultantDTO);
+    assertThrows(
+        CustomValidationHttpStatusException.class,
+        () -> {
+          when(rocketChatService.getUserID(anyString(), anyString(), anyBoolean()))
+              .thenReturn(DUMMY_RC_ID);
+          KeycloakCreateUserResponseDTO keycloakResponse =
+              easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
+          keycloakResponse.setUserId(null);
+          when(keycloakService.createKeycloakUser(any(), anyString(), any()))
+              .thenReturn(keycloakResponse);
+          CreateConsultantDTO createConsultantDTO =
+              this.easyRandom.nextObject(CreateConsultantDTO.class);
+
+          this.createConsultantSaga.createNewConsultant(createConsultantDTO);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/CreateConsultantSagaTenantAwareIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/CreateConsultantSagaTenantAwareIT.java
index 2624605f1..8f2b508ad 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/CreateConsultantSagaTenantAwareIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/CreateConsultantSagaTenantAwareIT.java
@@ -4,6 +4,7 @@
 import static de.caritas.cob.userservice.api.config.auth.UserRole.GROUP_CHAT_CONSULTANT;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyBoolean;
 import static org.mockito.ArgumentMatchers.anyString;
@@ -29,9 +30,8 @@
 import de.caritas.cob.userservice.tenantadminservice.generated.web.model.Licensing;
 import de.caritas.cob.userservice.tenantadminservice.generated.web.model.TenantDTO;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
 import org.junit.jupiter.api.AfterEach;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
@@ -39,11 +39,9 @@
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.test.util.ReflectionTestUtils;
 import org.springframework.transaction.annotation.Transactional;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -73,16 +71,21 @@ public void tearDown() {
     TenantContext.clear();
   }
 
-  @Test(expected = CustomValidationHttpStatusException.class)
+  @Test
   public void
       createNewConsultant_Should_throwCustomValidationHttpStatusException_When_LicensesAreExceeded() {
-    // given
-    givenTenantApiCall();
-    createConsultant("username1");
-    createConsultant("username2");
-    CreateConsultantDTO createConsultantDTO = this.easyRandom.nextObject(CreateConsultantDTO.class);
-    this.createConsultantSaga.createNewConsultant(createConsultantDTO);
-    rollbackDBState();
+    assertThrows(
+        CustomValidationHttpStatusException.class,
+        () -> {
+          // given
+          givenTenantApiCall();
+          createConsultant("username1");
+          createConsultant("username2");
+          CreateConsultantDTO createConsultantDTO =
+              this.easyRandom.nextObject(CreateConsultantDTO.class);
+          this.createConsultantSaga.createNewConsultant(createConsultantDTO);
+          rollbackDBState();
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceIT.java
index 7a57aa07d..2c45294fc 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceIT.java
@@ -7,7 +7,8 @@
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hibernate.search.util.impl.CollectionHelper.asSet;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.timeout;
@@ -42,8 +43,7 @@
 import java.util.List;
 import java.util.Set;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -52,9 +52,7 @@
 import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.annotation.DirtiesContext.ClassMode;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -274,93 +272,115 @@ private Session createSessionWithoutConsultant(Long agencyId, SessionStatus sess
     return this.sessionRepository.save(session);
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       createConsultantAgencyRelations_Should_throwBadRequestException_When_consultantDoesNotExist() {
-    this.consultantAgencyRelationCreatorService.createConsultantAgencyRelations(
-        "invalid", asSet(1L), asSet("role"), null);
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          this.consultantAgencyRelationCreatorService.createConsultantAgencyRelations(
+              "invalid", asSet(1L), asSet("role"), null);
+        });
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       createNewConsultantAgency_Should_throwBadRequestException_When_consultantHasNotExpectedRole() {
-    Consultant consultant = createConsultantWithoutAgencyAndSession();
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          Consultant consultant = createConsultantWithoutAgencyAndSession();
 
-    CreateConsultantAgencyDTO createConsultantAgencyDTO = new CreateConsultantAgencyDTO();
-    when(keycloakService.userHasRole(any(), any())).thenReturn(false);
+          CreateConsultantAgencyDTO createConsultantAgencyDTO = new CreateConsultantAgencyDTO();
+          when(keycloakService.userHasRole(any(), any())).thenReturn(false);
 
-    this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
-        consultant.getId(), createConsultantAgencyDTO);
+          this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
+              consultant.getId(), createConsultantAgencyDTO);
+        });
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       createNewConsultantAgency_Should_throwBadRequestException_When_agencyServiceReturnesNullForAgency() {
-    Consultant consultant = createConsultantWithoutAgencyAndSession();
-
-    CreateConsultantAgencyDTO createConsultantAgencyDTO =
-        new CreateConsultantAgencyDTO().roleSetKey("valid role set");
-    when(keycloakService.userHasRole(any(), any())).thenReturn(true);
-    when(this.agencyService.getAgencyWithoutCaching(any())).thenReturn(null);
-
-    this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
-        consultant.getId(), createConsultantAgencyDTO);
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          Consultant consultant = createConsultantWithoutAgencyAndSession();
+
+          CreateConsultantAgencyDTO createConsultantAgencyDTO =
+              new CreateConsultantAgencyDTO().roleSetKey("valid role set");
+          when(keycloakService.userHasRole(any(), any())).thenReturn(true);
+          when(this.agencyService.getAgencyWithoutCaching(any())).thenReturn(null);
+
+          this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
+              consultant.getId(), createConsultantAgencyDTO);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createNewConsultantAgency_Should_throwInternalServerErrorException_When_agencyServiceThrowsAgencyServiceHelperException() {
-    Consultant consultant = createConsultantWithoutAgencyAndSession();
-
-    CreateConsultantAgencyDTO createConsultantAgencyDTO =
-        new CreateConsultantAgencyDTO().roleSetKey("valid role set");
-    when(keycloakService.userHasRole(any(), any())).thenReturn(true);
-    when(agencyService.getAgencyWithoutCaching(any()))
-        .thenThrow(new InternalServerErrorException(""));
-
-    this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
-        consultant.getId(), createConsultantAgencyDTO);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          Consultant consultant = createConsultantWithoutAgencyAndSession();
+
+          CreateConsultantAgencyDTO createConsultantAgencyDTO =
+              new CreateConsultantAgencyDTO().roleSetKey("valid role set");
+          when(keycloakService.userHasRole(any(), any())).thenReturn(true);
+          when(agencyService.getAgencyWithoutCaching(any()))
+              .thenThrow(new InternalServerErrorException(""));
+
+          this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
+              consultant.getId(), createConsultantAgencyDTO);
+        });
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       createNewConsultantAgency_Should_throwBadRequestException_When_agencyTypeIsU25AndConsultantHasAnotherConsultingTypeAssigned() {
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          AgencyDTO emigrationAgency = new AgencyDTO().consultingType(17);
 
-    AgencyDTO emigrationAgency = new AgencyDTO().consultingType(17);
-
-    AgencyDTO agencyDTO = new AgencyDTO().consultingType(1).id(2L);
+          AgencyDTO agencyDTO = new AgencyDTO().consultingType(1).id(2L);
 
-    when(agencyService.getAgencyWithoutCaching(1731L)).thenReturn(emigrationAgency);
-    when(agencyService.getAgencyWithoutCaching(2L)).thenReturn(agencyDTO);
-    when(keycloakService.userHasRole(any(), any())).thenReturn(true);
-    when(consultingTypeManager.isConsultantBoundedToAgency(1)).thenReturn(true);
+          when(agencyService.getAgencyWithoutCaching(1731L)).thenReturn(emigrationAgency);
+          when(agencyService.getAgencyWithoutCaching(2L)).thenReturn(agencyDTO);
+          when(keycloakService.userHasRole(any(), any())).thenReturn(true);
+          when(consultingTypeManager.isConsultantBoundedToAgency(1)).thenReturn(true);
 
-    CreateConsultantAgencyDTO createConsultantAgencyDTO =
-        new CreateConsultantAgencyDTO().roleSetKey("valid role set").agencyId(2L);
+          CreateConsultantAgencyDTO createConsultantAgencyDTO =
+              new CreateConsultantAgencyDTO().roleSetKey("valid role set").agencyId(2L);
 
-    String consultantIdWIthEmigrationAgency = "0b3b1cc6-be98-4787-aa56-212259d811b9";
-    this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
-        consultantIdWIthEmigrationAgency, createConsultantAgencyDTO);
+          String consultantIdWIthEmigrationAgency = "0b3b1cc6-be98-4787-aa56-212259d811b9";
+          this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
+              consultantIdWIthEmigrationAgency, createConsultantAgencyDTO);
+        });
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       createNewConsultantAgency_Should_throwBadRequestException_When_agencyTypeIsKreuzbundAndConsultantHasAnotherConsultingTypeAssigned() {
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          AgencyDTO emigrationAgency = new AgencyDTO().consultingType(17);
 
-    AgencyDTO emigrationAgency = new AgencyDTO().consultingType(17);
-
-    AgencyDTO agencyDTO = new AgencyDTO().consultingType(15).id(2L);
+          AgencyDTO agencyDTO = new AgencyDTO().consultingType(15).id(2L);
 
-    when(agencyService.getAgencyWithoutCaching(1731L)).thenReturn(emigrationAgency);
-    when(agencyService.getAgencyWithoutCaching(2L)).thenReturn(agencyDTO);
-    when(keycloakService.userHasRole(any(), any())).thenReturn(true);
-    when(consultingTypeManager.isConsultantBoundedToAgency(15)).thenReturn(true);
+          when(agencyService.getAgencyWithoutCaching(1731L)).thenReturn(emigrationAgency);
+          when(agencyService.getAgencyWithoutCaching(2L)).thenReturn(agencyDTO);
+          when(keycloakService.userHasRole(any(), any())).thenReturn(true);
+          when(consultingTypeManager.isConsultantBoundedToAgency(15)).thenReturn(true);
 
-    CreateConsultantAgencyDTO createConsultantAgencyDTO =
-        new CreateConsultantAgencyDTO().roleSetKey("valid role set").agencyId(2L);
+          CreateConsultantAgencyDTO createConsultantAgencyDTO =
+              new CreateConsultantAgencyDTO().roleSetKey("valid role set").agencyId(2L);
 
-    this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
-        "0b3b1cc6-be98-4787-aa56-212259d811b9", createConsultantAgencyDTO);
+          this.consultantAgencyRelationCreatorService.createNewConsultantAgency(
+              "0b3b1cc6-be98-4787-aa56-212259d811b9", createConsultantAgencyDTO);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceTenantAwareIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceTenantAwareIT.java
index 9d11c356d..a30681171 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceTenantAwareIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceTenantAwareIT.java
@@ -37,10 +37,9 @@
 import java.util.List;
 import java.util.Set;
 import org.jeasy.random.EasyRandom;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -49,11 +48,9 @@
 import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.annotation.DirtiesContext.ClassMode;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.transaction.annotation.Propagation;
 import org.springframework.transaction.annotation.Transactional;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -84,12 +81,12 @@ public class ConsultantAgencyRelationCreatorServiceTenantAwareIT {
 
   @MockBean private ConsultingTypeManager consultingTypeManager;
 
-  @Before
+  @BeforeEach
   public void beforeTests() {
     TenantContext.setCurrentTenant(1L);
   }
 
-  @After
+  @AfterEach
   public void afterTests() {
     TenantContext.clear();
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceTest.java
index d59aba22b..ff21a9edf 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ConsultantAgencyRelationCreatorServiceTest.java
@@ -15,13 +15,13 @@
 import de.caritas.cob.userservice.api.service.agency.AgencyService;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantAgencyRelationCreatorServiceTest {
 
   private final EasyRandom easyRandom = new EasyRandom();
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ImportRecordAgencyCreationInputAdapterTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ImportRecordAgencyCreationInputAdapterTest.java
index fc43dd024..1afad8d6b 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ImportRecordAgencyCreationInputAdapterTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/create/agencyrelation/ImportRecordAgencyCreationInputAdapterTest.java
@@ -5,7 +5,7 @@
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hibernate.search.util.impl.CollectionHelper.asSet;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class ImportRecordAgencyCreationInputAdapterTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/delete/ConsultantPreDeletionServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/delete/ConsultantPreDeletionServiceTest.java
index cbe90a169..2f26057bd 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/delete/ConsultantPreDeletionServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/delete/ConsultantPreDeletionServiceTest.java
@@ -8,7 +8,7 @@
 import static java.util.Objects.requireNonNull;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
@@ -23,13 +23,13 @@
 import de.caritas.cob.userservice.api.model.Session;
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantPreDeletionServiceTest {
 
   private static final Boolean FORCE_DELETE_SESSIONS = false;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceBase.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceBase.java
index 3e691e767..ab6fba30e 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceBase.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceBase.java
@@ -5,7 +5,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.fail;
 
 import de.caritas.cob.userservice.api.adapters.rocketchat.RocketChatService;
 import de.caritas.cob.userservice.api.adapters.web.dto.UpdateAdminConsultantDTO;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceIT.java
index e5f212180..ba6418ddd 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceIT.java
@@ -1,15 +1,12 @@
 package de.caritas.cob.userservice.api.admin.service.consultant.update;
 
 import de.caritas.cob.userservice.api.UserServiceApplication;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceTenantAwareIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceTenantAwareIT.java
index 1fdd79125..28e0464fb 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceTenantAwareIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceTenantAwareIT.java
@@ -11,19 +11,16 @@
 import de.caritas.cob.userservice.api.tenant.TenantContext;
 import java.util.Set;
 import org.jeasy.random.EasyRandom;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.transaction.annotation.Transactional;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -40,12 +37,12 @@ public class ConsultantUpdateServiceTenantAwareIT extends ConsultantUpdateServic
   @Autowired ConsultantAgencyRepository consultantAgencyRepository;
   private Set<String> consultantsToRemove = Sets.newHashSet();
 
-  @Before
+  @BeforeEach
   public void beforeTests() {
     TenantContext.setCurrentTenant(1L);
   }
 
-  @After
+  @AfterEach
   public void afterTests() {
     consultantsToRemove.stream().forEach(id -> consultantRepository.deleteById(id));
     TenantContext.clear();
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceTest.java
index 633da57f3..d70aebdc0 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/update/ConsultantUpdateServiceTest.java
@@ -1,5 +1,6 @@
 package de.caritas.cob.userservice.api.admin.service.consultant.update;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
@@ -19,14 +20,14 @@
 import de.caritas.cob.userservice.api.service.appointment.AppointmentService;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantUpdateServiceTest {
 
   @InjectMocks private ConsultantUpdateService consultantUpdateService;
@@ -41,12 +42,16 @@ public class ConsultantUpdateServiceTest {
 
   @Mock private AppointmentService appointmentService;
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       updateConsultant_Should_throwBadRequestException_When_givenConsultantIdDoesNotExist() {
-    when(this.consultantService.getConsultant(any())).thenReturn(Optional.empty());
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          when(this.consultantService.getConsultant(any())).thenReturn(Optional.empty());
 
-    this.consultantUpdateService.updateConsultant("", mock(UpdateAdminConsultantDTO.class));
+          this.consultantUpdateService.updateConsultant("", mock(UpdateAdminConsultantDTO.class));
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/validation/UserAccountInputValidatorTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/validation/UserAccountInputValidatorTest.java
index b37976cab..ef3806053 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/validation/UserAccountInputValidatorTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/consultant/validation/UserAccountInputValidatorTest.java
@@ -6,7 +6,8 @@
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hibernate.validator.internal.util.CollectionHelper.asSet;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
@@ -18,13 +19,13 @@
 import javax.validation.Path;
 import javax.validation.Validator;
 import org.hibernate.validator.internal.engine.ConstraintViolationImpl;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class UserAccountInputValidatorTest {
 
   @InjectMocks private UserAccountInputValidator userAccountInputValidator;
@@ -87,11 +88,15 @@ public void validateKeycloakResponse_ShouldNot_throwException_When_keycloakRespo
     }
   }
 
-  @Test(expected = KeycloakException.class)
+  @Test
   public void validateKeycloakResponse_Should_throwKeycloakException_When_userIdIsNull() {
-    KeycloakCreateUserResponseDTO responseDTO = new KeycloakCreateUserResponseDTO();
+    assertThrows(
+        KeycloakException.class,
+        () -> {
+          KeycloakCreateUserResponseDTO responseDTO = new KeycloakCreateUserResponseDTO();
 
-    this.userAccountInputValidator.validateKeycloakResponse(responseDTO);
+          this.userAccountInputValidator.validateKeycloakResponse(responseDTO);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatAddToGroupOperationServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatAddToGroupOperationServiceTest.java
index 560a29f7d..94ff9248f 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatAddToGroupOperationServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatAddToGroupOperationServiceTest.java
@@ -3,7 +3,8 @@
 import static java.util.Collections.singletonList;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.atLeastOnce;
@@ -22,12 +23,12 @@
 import de.caritas.cob.userservice.api.model.Session.SessionStatus;
 import java.util.function.Consumer;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocketChatAddToGroupOperationServiceTest {
 
   private final EasyRandom easyRandom = new EasyRandom();
@@ -92,24 +93,27 @@ public class RocketChatAddToGroupOperationServiceTest {
     }
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       addToGroupsOrRollbackOnFailure_Should_logErrorMessage_When_removeOfTechnicalUserFailes() {
-
-    Session session = easyRandom.nextObject(Session.class);
-    session.setStatus(SessionStatus.NEW);
-    Consultant consultant = easyRandom.nextObject(Consultant.class);
-    doThrow(new RuntimeException(""))
-        .when(this.rocketChatFacade)
-        .addUserToRocketChatGroup(anyString(), anyString());
-
-    RocketChatAddToGroupOperationService.getInstance(
-            this.rocketChatFacade, this.keycloakService, logMethod, consultingTypeManager)
-        .onSessions(singletonList(session))
-        .withConsultant(consultant)
-        .addToGroupsOrRollbackOnFailure();
-
-    verify(logMethod, atLeastOnce()).accept(anyString());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          Session session = easyRandom.nextObject(Session.class);
+          session.setStatus(SessionStatus.NEW);
+          Consultant consultant = easyRandom.nextObject(Consultant.class);
+          doThrow(new RuntimeException(""))
+              .when(this.rocketChatFacade)
+              .addUserToRocketChatGroup(anyString(), anyString());
+
+          RocketChatAddToGroupOperationService.getInstance(
+                  this.rocketChatFacade, this.keycloakService, logMethod, consultingTypeManager)
+              .onSessions(singletonList(session))
+              .withConsultant(consultant)
+              .addToGroupsOrRollbackOnFailure();
+
+          verify(logMethod, atLeastOnce()).accept(anyString());
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatOperationConditionProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatOperationConditionProviderTest.java
index 95a6f6b5d..1ea4d4164 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatOperationConditionProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatOperationConditionProviderTest.java
@@ -12,13 +12,13 @@
 import de.caritas.cob.userservice.api.model.Consultant;
 import de.caritas.cob.userservice.api.model.Session;
 import de.caritas.cob.userservice.api.model.Session.SessionStatus;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocketChatOperationConditionProviderTest {
 
   @InjectMocks private RocketChatOperationConditionProvider conditionProvider;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatRemoveFromGroupOperationServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatRemoveFromGroupOperationServiceTest.java
index 9dd34df30..07526d5f7 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatRemoveFromGroupOperationServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/rocketchat/RocketChatRemoveFromGroupOperationServiceTest.java
@@ -3,7 +3,7 @@
 import static java.util.Collections.singletonList;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.containsString;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.doThrow;
@@ -23,13 +23,13 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocketChatRemoveFromGroupOperationServiceTest {
 
   private RocketChatRemoveFromGroupOperationService removeService;
@@ -44,7 +44,7 @@ public class RocketChatRemoveFromGroupOperationServiceTest {
 
   @Mock private ConsultingTypeManager consultingTypeManager;
 
-  @Before
+  @BeforeEach
   public void setup() {
     Map<Session, List<Consultant>> sessionConsultants = new HashMap<>();
     sessionConsultants.put(session, singletonList(consultant));
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/SessionAdminServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/SessionAdminServiceIT.java
index a3ae92ad7..2b0bc14c6 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/SessionAdminServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/SessionAdminServiceIT.java
@@ -9,16 +9,13 @@
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionAdminDTO;
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionAdminResultDTO;
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionFilter;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/SessionAdminServiceTenantAwareIT.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/SessionAdminServiceTenantAwareIT.java
index 36e8570f7..a2059ce9f 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/SessionAdminServiceTenantAwareIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/SessionAdminServiceTenantAwareIT.java
@@ -7,19 +7,16 @@
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionAdminResultDTO;
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionFilter;
 import de.caritas.cob.userservice.api.tenant.TenantContext;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.transaction.annotation.Transactional;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -32,12 +29,12 @@ public class SessionAdminServiceTenantAwareIT {
 
   @Autowired private SessionAdminService sessionAdminService;
 
-  @Before
+  @BeforeEach
   public void beforeTests() {
     TenantContext.setCurrentTenant(1L);
   }
 
-  @After
+  @AfterEach
   public void afterTests() {
     TenantContext.clear();
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AgencySessionPageProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AgencySessionPageProviderTest.java
index a509992e4..14b808823 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AgencySessionPageProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AgencySessionPageProviderTest.java
@@ -8,15 +8,15 @@
 
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionFilter;
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.data.domain.PageRequest;
 
-@RunWith(MockitoJUnitRunner.class)
-public class AgencySessionPageProviderTest {
+@ExtendWith(MockitoExtension.class)
+class AgencySessionPageProviderTest {
 
   @InjectMocks private AgencySessionPageProvider agencySessionPageProvider;
 
@@ -25,7 +25,7 @@ public class AgencySessionPageProviderTest {
   @Mock private SessionFilter sessionFilter;
 
   @Test
-  public void supports_Should_returnTrue_When_agencyFilterIsSet() {
+  void supports_Should_returnTrue_When_agencyFilterIsSet() {
     when(this.sessionFilter.getAgency()).thenReturn(1);
 
     boolean supports = this.agencySessionPageProvider.isSupported();
@@ -34,7 +34,7 @@ public void supports_Should_returnTrue_When_agencyFilterIsSet() {
   }
 
   @Test
-  public void supports_Should_returnFalse_When_agencyFilterIsNotSet() {
+  void supports_Should_returnFalse_When_agencyFilterIsNotSet() {
     when(this.sessionFilter.getAgency()).thenReturn(null);
 
     boolean supports = this.agencySessionPageProvider.isSupported();
@@ -43,7 +43,7 @@ public void supports_Should_returnFalse_When_agencyFilterIsNotSet() {
   }
 
   @Test
-  public void executeQuery_Should_executeQueryOnRepository_When_pagebleIsGiven() {
+  void executeQuery_Should_executeQueryOnRepository_When_pagebleIsGiven() {
     when(this.sessionFilter.getAgency()).thenReturn(1);
     PageRequest pageable = PageRequest.of(0, 1);
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AllSessionPageProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AllSessionPageProviderTest.java
index b028636d5..8b25dceb6 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AllSessionPageProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AllSessionPageProviderTest.java
@@ -6,29 +6,29 @@
 import static org.mockito.Mockito.verify;
 
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.data.domain.PageRequest;
 
-@RunWith(MockitoJUnitRunner.class)
-public class AllSessionPageProviderTest {
+@ExtendWith(MockitoExtension.class)
+class AllSessionPageProviderTest {
 
   @InjectMocks private AllSessionPageProvider allSessionPageProvider;
 
   @Mock private SessionRepository sessionRepository;
 
   @Test
-  public void supports_Should_returnTrue() {
+  void supports_Should_returnTrue() {
     boolean supports = this.allSessionPageProvider.isSupported();
 
     assertThat(supports, is(true));
   }
 
   @Test
-  public void executeQuery_Should_executeQueryOnRepository_When_pagebleIsGiven() {
+  void executeQuery_Should_executeQueryOnRepository_When_pagebleIsGiven() {
     PageRequest pageable = PageRequest.of(0, 1);
 
     this.allSessionPageProvider.executeQuery(pageable);
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AskerSessionPageProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AskerSessionPageProviderTest.java
index 9728b6dc8..d046b19da 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AskerSessionPageProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/AskerSessionPageProviderTest.java
@@ -8,15 +8,15 @@
 
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionFilter;
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.data.domain.PageRequest;
 
-@RunWith(MockitoJUnitRunner.class)
-public class AskerSessionPageProviderTest {
+@ExtendWith(MockitoExtension.class)
+class AskerSessionPageProviderTest {
 
   @InjectMocks private AskerSessionPageProvider askerSessionPageProvider;
 
@@ -25,7 +25,7 @@ public class AskerSessionPageProviderTest {
   @Mock private SessionFilter sessionFilter;
 
   @Test
-  public void supports_Should_returnTrue_When_askerFilterIsSet() {
+  void supports_Should_returnTrue_When_askerFilterIsSet() {
     when(this.sessionFilter.getAsker()).thenReturn("asker");
 
     boolean supports = this.askerSessionPageProvider.isSupported();
@@ -34,7 +34,7 @@ public void supports_Should_returnTrue_When_askerFilterIsSet() {
   }
 
   @Test
-  public void supports_Should_returnFalse_When_askerFilterIsNotSet() {
+  void supports_Should_returnFalse_When_askerFilterIsNotSet() {
     when(this.sessionFilter.getAsker()).thenReturn(null);
 
     boolean supports = this.askerSessionPageProvider.isSupported();
@@ -43,7 +43,7 @@ public void supports_Should_returnFalse_When_askerFilterIsNotSet() {
   }
 
   @Test
-  public void executeQuery_Should_executeQueryOnRepository_When_pagebleIsGiven() {
+  void executeQuery_Should_executeQueryOnRepository_When_pagebleIsGiven() {
     when(this.sessionFilter.getAsker()).thenReturn("asker");
     PageRequest pageable = PageRequest.of(0, 1);
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/ConsultantSessionPageProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/ConsultantSessionPageProviderTest.java
index a5baef4c2..bc79babc4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/ConsultantSessionPageProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/ConsultantSessionPageProviderTest.java
@@ -8,14 +8,14 @@
 
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionFilter;
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.data.domain.PageRequest;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantSessionPageProviderTest {
 
   @InjectMocks private ConsultantSessionPageProvider consultantSessionPageProvider;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/ConsultingTypeSessionPageProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/ConsultingTypeSessionPageProviderTest.java
index eec41d338..b1bb6e79a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/ConsultingTypeSessionPageProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/ConsultingTypeSessionPageProviderTest.java
@@ -8,14 +8,14 @@
 
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionFilter;
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.data.domain.PageRequest;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultingTypeSessionPageProviderTest {
 
   @InjectMocks private ConsultingTypeSessionPageProvider consultingTypeSessionPageProvider;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/PageProviderFactoryTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/PageProviderFactoryTest.java
index 22c1edb92..d150e42a4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/PageProviderFactoryTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/session/pageprovider/PageProviderFactoryTest.java
@@ -5,12 +5,12 @@
 
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionFilter;
 import de.caritas.cob.userservice.api.port.out.SessionRepository;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class PageProviderFactoryTest {
 
   @Mock private SessionRepository sessionRepository;
diff --git a/src/test/java/de/caritas/cob/userservice/api/admin/service/user/anonymous/AnonymousUsernameRegistryTest.java b/src/test/java/de/caritas/cob/userservice/api/admin/service/user/anonymous/AnonymousUsernameRegistryTest.java
index 2c7b5a690..e04bffbdf 100644
--- a/src/test/java/de/caritas/cob/userservice/api/admin/service/user/anonymous/AnonymousUsernameRegistryTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/admin/service/user/anonymous/AnonymousUsernameRegistryTest.java
@@ -20,30 +20,32 @@
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Optional;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoSettings;
 import org.powermock.modules.junit4.PowerMockRunner;
 
 @RunWith(PowerMockRunner.class)
-public class AnonymousUsernameRegistryTest {
+@MockitoSettings(strictness = org.mockito.quality.Strictness.LENIENT)
+class AnonymousUsernameRegistryTest {
 
   @InjectMocks private AnonymousUsernameRegistry anonymousUsernameRegistry;
   @Mock private UserService userService;
   @Mock private ConsultantService consultantService;
   @Mock private UsernameTranscoder usernameTranscoder;
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void setUp() {
     setField(anonymousUsernameRegistry, "usernameTranscoder", usernameTranscoder);
     setField(anonymousUsernameRegistry, "usernamePrefix", "Ratsuchende_r ");
   }
 
   @Test
-  public void
+  void
       generateUniqueUsername_Should_GenerateUsernameWithMissingIdOfList_When_MissingUserIdNotExistingInDb() {
     LinkedList<Integer> idRegistryListWithoutThree = new LinkedList<>(List.of(1, 2, 4, 5));
     setIdRegistryField(idRegistryListWithoutThree);
@@ -61,7 +63,7 @@ private void setIdRegistryField(LinkedList<Integer> idRegistryListWithoutThree)
   }
 
   @Test
-  public void
+  void
       generateUniqueUsername_Should_GenerateUsernameWithSecondMissingIdOfList_When_FirstMissingUserIdIsExistingInDb() {
     LinkedList<Integer> idRegistryListWithoutThree = new LinkedList<>(List.of(1, 2, 4, 6));
     setIdRegistryField(idRegistryListWithoutThree);
@@ -76,7 +78,7 @@ private void setIdRegistryField(LinkedList<Integer> idRegistryListWithoutThree)
   }
 
   @Test
-  public void
+  void
       generateUniqueUsername_Should_GenerateUsernameWithIdOne_When_ListIsEmptyAndUserNotExistingInDb() {
     LinkedList<Integer> idRegistryListWithoutThree = new LinkedList<>();
     setIdRegistryField(idRegistryListWithoutThree);
@@ -90,7 +92,7 @@ private void setIdRegistryField(LinkedList<Integer> idRegistryListWithoutThree)
   }
 
   @Test
-  public void
+  void
       generateUniqueUsername_Should_GenerateUsernameWithIdGreaterThanBiggestListId_When_ListContainsContiguousIdsAndUserNotExistingInDb() {
     LinkedList<Integer> idRegistryListWithoutThree = new LinkedList<>(List.of(1, 2, 3, 4, 5));
     setIdRegistryField(idRegistryListWithoutThree);
@@ -104,7 +106,7 @@ private void setIdRegistryField(LinkedList<Integer> idRegistryListWithoutThree)
   }
 
   @Test
-  public void
+  void
       generateUniqueUsername_Should_GenerateUsernameWithIdGreaterThanBiggestListId_When_MissingIdsOfListHaveExistingUsersInDb() {
     LinkedList<Integer> idRegistryListWithoutThree = new LinkedList<>(List.of(1, 2, 4, 6));
     setIdRegistryField(idRegistryListWithoutThree);
@@ -120,7 +122,7 @@ private void setIdRegistryField(LinkedList<Integer> idRegistryListWithoutThree)
   }
 
   @Test
-  public void
+  void
       generateUniqueUsername_Should_GenerateUsernameWithIdGreaterThanBiggestListId_When_MissingIdsOfListHaveExistingConsultantsInDb() {
     LinkedList<Integer> idRegistryListWithoutThree = new LinkedList<>(List.of(1, 2, 4, 6));
     setIdRegistryField(idRegistryListWithoutThree);
@@ -138,7 +140,7 @@ private void setIdRegistryField(LinkedList<Integer> idRegistryListWithoutThree)
   }
 
   @Test
-  public void
+  void
       removeRegistryIdByUsername_Should_RemoveIdFromRegistry_When_UsernameMatchesUsernamePattern() {
     String usernameToDelete = "Ratsuchende_r 2";
 
@@ -159,7 +161,7 @@ private List<Integer> getIdRegistryField() {
   }
 
   @Test
-  public void
+  void
       removeRegistryIdByUsername_Should_NotModifyTheRegistry_When_UsernameDoesNotMatchUsernamePattern() {
     String usernameNotMatchingPattern = "something else";
 
@@ -176,7 +178,7 @@ private List<Integer> getIdRegistryField() {
   }
 
   @Test
-  public void
+  void
       removeRegistryIdByUsername_Should_NotModifyTheRegistry_When_UsernameDoesMatchUsernamePatternButHasNotExistingNumber() {
     String usernameWithNotExistingId = "Ratsuchende_r 3";
 
@@ -193,7 +195,7 @@ private List<Integer> getIdRegistryField() {
   }
 
   @Test
-  public void removeRegistryIdByUsername_Should_NotModifyTheRegistry_When_EmptyValuePassed() {
+  void removeRegistryIdByUsername_Should_NotModifyTheRegistry_When_EmptyValuePassed() {
     LinkedList<Integer> idRegistryListWithoutThree = new LinkedList<>(List.of(1, 2, 4, 5));
     setIdRegistryField(idRegistryListWithoutThree);
     when(userService.findUserByUsername(any())).thenReturn(Optional.empty());
@@ -209,7 +211,7 @@ public void removeRegistryIdByUsername_Should_NotModifyTheRegistry_When_EmptyVal
   }
 
   @Test
-  public void removeRegistryIdByUsername_Should_NotModifyTheRegistry_When_NullPassed() {
+  void removeRegistryIdByUsername_Should_NotModifyTheRegistry_When_NullPassed() {
     LinkedList<Integer> idRegistryListWithoutThree = new LinkedList<>(List.of(1, 2, 4, 5));
     setIdRegistryField(idRegistryListWithoutThree);
     when(userService.findUserByUsername(any())).thenReturn(Optional.empty());
diff --git a/src/test/java/de/caritas/cob/userservice/api/config/auth/AuthorityTest.java b/src/test/java/de/caritas/cob/userservice/api/config/auth/AuthorityTest.java
index 17cb21629..237ffa21e 100644
--- a/src/test/java/de/caritas/cob/userservice/api/config/auth/AuthorityTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/config/auth/AuthorityTest.java
@@ -7,17 +7,15 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.containsInAnyOrder;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 
 import de.caritas.cob.userservice.api.config.auth.Authority.AuthorityValue;
 import java.util.List;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class AuthorityTest {
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/config/auth/RoleAuthorizationAuthorityMapperTest.java b/src/test/java/de/caritas/cob/userservice/api/config/auth/RoleAuthorizationAuthorityMapperTest.java
index c0e050e2e..91d52c4cd 100644
--- a/src/test/java/de/caritas/cob/userservice/api/config/auth/RoleAuthorizationAuthorityMapperTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/config/auth/RoleAuthorizationAuthorityMapperTest.java
@@ -9,18 +9,18 @@
 import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.keycloak.adapters.RefreshableKeycloakSecurityContext;
 import org.keycloak.adapters.spi.KeycloakAccount;
 import org.keycloak.adapters.springsecurity.account.SimpleKeycloakAccount;
 import org.keycloak.adapters.springsecurity.authentication.KeycloakAuthenticationProvider;
 import org.keycloak.adapters.springsecurity.token.KeycloakAuthenticationToken;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.security.core.Authentication;
 import org.springframework.security.core.authority.SimpleGrantedAuthority;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RoleAuthorizationAuthorityMapperTest {
 
   private final KeycloakAuthenticationProvider provider = new KeycloakAuthenticationProvider();
diff --git a/src/test/java/de/caritas/cob/userservice/api/conversation/facade/AcceptAnonymousEnquiryFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/conversation/facade/AcceptAnonymousEnquiryFacadeTest.java
index 6da38f4fa..da460877d 100644
--- a/src/test/java/de/caritas/cob/userservice/api/conversation/facade/AcceptAnonymousEnquiryFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/conversation/facade/AcceptAnonymousEnquiryFacadeTest.java
@@ -1,5 +1,6 @@
 package de.caritas.cob.userservice.api.conversation.facade;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.times;
@@ -14,14 +15,14 @@
 import de.caritas.cob.userservice.api.service.user.UserAccountService;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
-public class AcceptAnonymousEnquiryFacadeTest {
+@ExtendWith(MockitoExtension.class)
+class AcceptAnonymousEnquiryFacadeTest {
 
   @InjectMocks private AcceptAnonymousEnquiryFacade acceptAnonymousEnquiryFacade;
 
@@ -34,7 +35,7 @@ public class AcceptAnonymousEnquiryFacadeTest {
   @Mock private UserAccountService userAccountService;
 
   @Test
-  public void acceptAnonymousEnquiry_Should_useServicesCorrectly_When_sessionExists() {
+  void acceptAnonymousEnquiry_Should_useServicesCorrectly_When_sessionExists() {
     Session session = new EasyRandom().nextObject(Session.class);
     when(this.sessionService.getSession(session.getId())).thenReturn(Optional.of(session));
 
@@ -46,8 +47,12 @@ public void acceptAnonymousEnquiry_Should_useServicesCorrectly_When_sessionExist
         .sendAcceptAnonymousEnquiryEventToUser(session.getUser().getUserId());
   }
 
-  @Test(expected = NotFoundException.class)
-  public void acceptAnonymousEnquiry_Should_throwNotFoundException_When_sessionDoesNotExist() {
-    this.acceptAnonymousEnquiryFacade.acceptAnonymousEnquiry(1L);
+  @Test
+  void acceptAnonymousEnquiry_Should_throwNotFoundException_When_sessionDoesNotExist() {
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          this.acceptAnonymousEnquiryFacade.acceptAnonymousEnquiry(1L);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/conversation/provider/AnonymousEnquiryConversationListProviderIT.java b/src/test/java/de/caritas/cob/userservice/api/conversation/provider/AnonymousEnquiryConversationListProviderIT.java
index c1fc1401f..55da81287 100644
--- a/src/test/java/de/caritas/cob/userservice/api/conversation/provider/AnonymousEnquiryConversationListProviderIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/conversation/provider/AnonymousEnquiryConversationListProviderIT.java
@@ -35,10 +35,9 @@
 import java.util.stream.Collectors;
 import org.apache.commons.collections4.iterators.PeekingIterator;
 import org.jeasy.random.EasyRandom;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -46,14 +45,12 @@
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.context.annotation.Import;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
 @Import({ConsultingTypeManagerTestConfig.class})
-public class AnonymousEnquiryConversationListProviderIT {
+class AnonymousEnquiryConversationListProviderIT {
 
   @Autowired
   private AnonymousEnquiryConversationListProvider anonymousEnquiryConversationListProvider;
@@ -66,8 +63,8 @@ public class AnonymousEnquiryConversationListProviderIT {
 
   @MockBean private UserAccountService userAccountProvider;
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void setup() {
     Consultant consultant = mock(Consultant.class);
     ConsultantAgency consultantAgency = mock(ConsultantAgency.class);
     when(consultant.getConsultantAgencies()).thenReturn(asSet(consultantAgency));
@@ -76,14 +73,13 @@ public void setup() {
     when(this.agencyService.getAgencies(any())).thenReturn(singletonList(agencyDTO));
   }
 
-  @After
-  public void cleanDatabase() {
+  @AfterEach
+  void cleanDatabase() {
     this.sessionRepository.deleteAll();
   }
 
   @Test
-  public void
-      buildConversations_Should_returnExpectedResponseDTO_When_consultantHasAnonymousEnquiries() {
+  void buildConversations_Should_returnExpectedResponseDTO_When_consultantHasAnonymousEnquiries() {
     saveAnonymousSessions(10);
     PageableListRequest request = PageableListRequest.builder().count(5).offset(0).build();
 
@@ -97,7 +93,7 @@ public void cleanDatabase() {
   }
 
   @Test
-  public void buildConversations_Should_returnExpectedElements_When_paginationParamsAreAtTheEnd() {
+  void buildConversations_Should_returnExpectedElements_When_paginationParamsAreAtTheEnd() {
     saveAnonymousSessions(10);
     PageableListRequest request = PageableListRequest.builder().count(3).offset(9).build();
 
@@ -111,7 +107,7 @@ public void buildConversations_Should_returnExpectedElements_When_paginationPara
   }
 
   @Test
-  public void buildConversations_Should_returnElementsInExpectedOrder() {
+  void buildConversations_Should_returnElementsInExpectedOrder() {
     saveAnonymousSessions(100);
     PageableListRequest request = PageableListRequest.builder().count(100).offset(0).build();
 
@@ -130,7 +126,7 @@ public void buildConversations_Should_returnElementsInExpectedOrder() {
   }
 
   @Test
-  public void providedType_Should_return_anonymousEnquiry() {
+  void providedType_Should_return_anonymousEnquiry() {
     ConversationListType conversationListType =
         this.anonymousEnquiryConversationListProvider.providedType();
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/conversation/provider/ArchivedSessionConversationListProviderTestIT.java b/src/test/java/de/caritas/cob/userservice/api/conversation/provider/ArchivedSessionConversationListProviderTestIT.java
index b0370f8fb..825466736 100644
--- a/src/test/java/de/caritas/cob/userservice/api/conversation/provider/ArchivedSessionConversationListProviderTestIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/conversation/provider/ArchivedSessionConversationListProviderTestIT.java
@@ -34,22 +34,19 @@
 import org.apache.commons.collections4.iterators.PeekingIterator;
 import org.apache.commons.lang3.RandomStringUtils;
 import org.jeasy.random.EasyRandom;
-import org.junit.After;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
-public class ArchivedSessionConversationListProviderTestIT {
+class ArchivedSessionConversationListProviderTestIT {
 
   @Autowired
   private ArchivedSessionConversationListProvider archivedSessionConversationListProvider;
@@ -64,16 +61,15 @@ public class ArchivedSessionConversationListProviderTestIT {
 
   @MockBean private UserAccountService userAccountProvider;
 
-  @After
-  public void cleanDatabase() {
+  @AfterEach
+  void cleanDatabase() {
     this.sessionRepository.deleteAll();
     this.consultantAgencyRepository.deleteAll();
     this.consultantRepository.deleteAll();
   }
 
   @Test
-  public void
-      buildConversations_Should_returnExpectedResponseDTO_When_consultantHasArchivedSessions() {
+  void buildConversations_Should_returnExpectedResponseDTO_When_consultantHasArchivedSessions() {
     saveTestData(10);
     PageableListRequest request = PageableListRequest.builder().count(5).offset(0).build();
 
@@ -87,7 +83,7 @@ public void cleanDatabase() {
   }
 
   @Test
-  public void buildConversations_Should_returnExpectedElements_When_paginationParamsAreAtTheEnd() {
+  void buildConversations_Should_returnExpectedElements_When_paginationParamsAreAtTheEnd() {
     saveTestData(10);
     PageableListRequest request = PageableListRequest.builder().count(3).offset(9).build();
 
@@ -101,7 +97,7 @@ public void buildConversations_Should_returnExpectedElements_When_paginationPara
   }
 
   @Test
-  public void buildConversations_Should_returnElementsInExpectedOrder() {
+  void buildConversations_Should_returnElementsInExpectedOrder() {
     saveTestData(100);
     PageableListRequest request = PageableListRequest.builder().count(100).offset(0).build();
 
@@ -120,7 +116,7 @@ public void buildConversations_Should_returnElementsInExpectedOrder() {
   }
 
   @Test
-  public void providedType_Should_return_archivedSession() {
+  void providedType_Should_return_archivedSession() {
     ConversationListType conversationListType =
         this.archivedSessionConversationListProvider.providedType();
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/conversation/provider/ArchivedTeamSessionConversationListProviderTestIT.java b/src/test/java/de/caritas/cob/userservice/api/conversation/provider/ArchivedTeamSessionConversationListProviderTestIT.java
index 043fac64f..5d4bc128a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/conversation/provider/ArchivedTeamSessionConversationListProviderTestIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/conversation/provider/ArchivedTeamSessionConversationListProviderTestIT.java
@@ -34,22 +34,19 @@
 import org.apache.commons.collections4.iterators.PeekingIterator;
 import org.apache.commons.lang3.RandomStringUtils;
 import org.jeasy.random.EasyRandom;
-import org.junit.After;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
-public class ArchivedTeamSessionConversationListProviderTestIT {
+class ArchivedTeamSessionConversationListProviderTestIT {
 
   @Autowired
   private ArchivedTeamSessionConversationListProvider archivedTeamSessionConversationListProvider;
@@ -64,15 +61,15 @@ public class ArchivedTeamSessionConversationListProviderTestIT {
 
   @MockBean private UserAccountService userAccountProvider;
 
-  @After
-  public void cleanDatabase() {
+  @AfterEach
+  void cleanDatabase() {
     this.sessionRepository.deleteAll();
     this.consultantAgencyRepository.deleteAll();
     this.consultantRepository.deleteAll();
   }
 
   @Test
-  public void
+  void
       buildConversations_Should_returnExpectedResponseDTO_When_consultantHasArchivedTeamSessions() {
     saveTestData(10);
     PageableListRequest request = PageableListRequest.builder().count(5).offset(0).build();
@@ -87,7 +84,7 @@ public void cleanDatabase() {
   }
 
   @Test
-  public void buildConversations_Should_returnExpectedElements_When_paginationParamsAreAtTheEnd() {
+  void buildConversations_Should_returnExpectedElements_When_paginationParamsAreAtTheEnd() {
     saveTestData(10);
     PageableListRequest request = PageableListRequest.builder().count(3).offset(9).build();
 
@@ -101,7 +98,7 @@ public void buildConversations_Should_returnExpectedElements_When_paginationPara
   }
 
   @Test
-  public void buildConversations_Should_returnElementsInExpectedOrder() {
+  void buildConversations_Should_returnElementsInExpectedOrder() {
     saveTestData(100);
     PageableListRequest request = PageableListRequest.builder().count(100).offset(0).build();
 
@@ -120,7 +117,7 @@ public void buildConversations_Should_returnElementsInExpectedOrder() {
   }
 
   @Test
-  public void providedType_Should_return_archivedTeamSession() {
+  void providedType_Should_return_archivedTeamSession() {
     ConversationListType conversationListType =
         this.archivedTeamSessionConversationListProvider.providedType();
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/conversation/provider/RegisteredEnquiryConversationListProviderIT.java b/src/test/java/de/caritas/cob/userservice/api/conversation/provider/RegisteredEnquiryConversationListProviderIT.java
index 38f0e49dd..ec1c47833 100644
--- a/src/test/java/de/caritas/cob/userservice/api/conversation/provider/RegisteredEnquiryConversationListProviderIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/conversation/provider/RegisteredEnquiryConversationListProviderIT.java
@@ -30,19 +30,16 @@
 import java.util.stream.Collectors;
 import org.apache.commons.collections4.iterators.PeekingIterator;
 import org.jeasy.random.EasyRandom;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -57,7 +54,7 @@ public class RegisteredEnquiryConversationListProviderIT {
 
   @MockBean private UserAccountService userAccountProvider;
 
-  @Before
+  @BeforeEach
   public void setup() {
     Consultant consultant = mock(Consultant.class);
     ConsultantAgency consultantAgency = mock(ConsultantAgency.class);
@@ -66,7 +63,7 @@ public void setup() {
     when(this.userAccountProvider.retrieveValidatedConsultant()).thenReturn(consultant);
   }
 
-  @After
+  @AfterEach
   public void cleanDatabase() {
     this.sessionRepository.deleteAll();
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/conversation/registry/ConversationListProviderRegistryTest.java b/src/test/java/de/caritas/cob/userservice/api/conversation/registry/ConversationListProviderRegistryTest.java
index a95f00f60..1e49b4fa3 100644
--- a/src/test/java/de/caritas/cob/userservice/api/conversation/registry/ConversationListProviderRegistryTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/conversation/registry/ConversationListProviderRegistryTest.java
@@ -4,6 +4,7 @@
 import static de.caritas.cob.userservice.api.conversation.model.ConversationListType.REGISTERED_ENQUIRY;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
@@ -13,23 +14,25 @@
 import de.caritas.cob.userservice.api.conversation.provider.RegisteredEnquiryConversationListProvider;
 import java.util.Map;
 import java.util.NoSuchElementException;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
 import org.springframework.context.ApplicationContext;
 
-@RunWith(MockitoJUnitRunner.class)
-public class ConversationListProviderRegistryTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = org.mockito.quality.Strictness.LENIENT)
+class ConversationListProviderRegistryTest {
 
   @InjectMocks private ConversationListProviderRegistry conversationListProviderRegistry;
 
   @Mock private ApplicationContext applicationContext;
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void setup() {
     ConversationListProvider anonymous = mock(AnonymousEnquiryConversationListProvider.class);
     when(anonymous.providedType()).thenReturn(ANONYMOUS_ENQUIRY);
     ConversationListProvider registered = mock(RegisteredEnquiryConversationListProvider.class);
@@ -38,13 +41,17 @@ public void setup() {
         .thenReturn(Map.of("anonymous", anonymous, "registered", registered));
   }
 
-  @Test(expected = NullPointerException.class)
-  public void findByConversationType_Should_throwNPE_When_registryIsNotInitialized() {
-    this.conversationListProviderRegistry.findByConversationType(ANONYMOUS_ENQUIRY);
+  @Test
+  void findByConversationType_Should_throwNPE_When_registryIsNotInitialized() {
+    assertThrows(
+        NullPointerException.class,
+        () -> {
+          this.conversationListProviderRegistry.findByConversationType(ANONYMOUS_ENQUIRY);
+        });
   }
 
   @Test
-  public void
+  void
       findByConversationType_Should_returnAnonymousEnquiryProvider_When_requestedTypeIsAnonymouseEnquiry() {
     this.conversationListProviderRegistry.initializeConversationSuppliers();
 
@@ -56,7 +63,7 @@ public void findByConversationType_Should_throwNPE_When_registryIsNotInitialized
   }
 
   @Test
-  public void
+  void
       findByConversationType_Should_returnregisteredEnquiryProvider_When_requestedTypeIsRegisteredEnquiry() {
     this.conversationListProviderRegistry.initializeConversationSuppliers();
 
@@ -67,10 +74,14 @@ public void findByConversationType_Should_throwNPE_When_registryIsNotInitialized
     assertThat(resultProvider.getClass(), is(RegisteredEnquiryConversationListProvider.class));
   }
 
-  @Test(expected = NoSuchElementException.class)
-  public void findByConversationType_Should_throwNoSuchElementException_When_requestedTypeIsNull() {
-    this.conversationListProviderRegistry.initializeConversationSuppliers();
+  @Test
+  void findByConversationType_Should_throwNoSuchElementException_When_requestedTypeIsNull() {
+    assertThrows(
+        NoSuchElementException.class,
+        () -> {
+          this.conversationListProviderRegistry.initializeConversationSuppliers();
 
-    this.conversationListProviderRegistry.findByConversationType(null);
+          this.conversationListProviderRegistry.findByConversationType(null);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/conversation/service1/user/anonymous/AnonymousUserCreatorServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/conversation/service1/user/anonymous/AnonymousUserCreatorServiceTest.java
index b72319e3b..0f4cdbbb4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/conversation/service1/user/anonymous/AnonymousUserCreatorServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/conversation/service1/user/anonymous/AnonymousUserCreatorServiceTest.java
@@ -30,16 +30,16 @@
 import de.caritas.cob.userservice.api.service.user.UserService;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
-public class AnonymousUserCreatorServiceTest {
+@ExtendWith(SpringExtension.class)
+class AnonymousUserCreatorServiceTest {
 
   @InjectMocks private AnonymousUserCreatorService anonymousUserCreatorService;
   @Mock private KeycloakService keycloakService;
@@ -54,42 +54,50 @@ public class AnonymousUserCreatorServiceTest {
 
   EasyRandom easyRandom = new EasyRandom();
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createAnonymousUser_Should_ThrowInternalServerErrorExceptionAndPerformRollback_When_KeycloakLoginFails() {
-    KeycloakCreateUserResponseDTO responseDTO =
-        easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
-    when(keycloakService.createKeycloakUser(any())).thenReturn(responseDTO);
-    when(keycloakService.loginUser(anyString(), anyString()))
-        .thenThrow(new BadRequestException(ERROR));
-
-    anonymousUserCreatorService.createAnonymousUser(USER_DTO_SUCHT);
-
-    verifyNoInteractions(rollbackFacade);
-    verifyNoInteractions(rocketChatService);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          KeycloakCreateUserResponseDTO responseDTO =
+              easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
+          when(keycloakService.createKeycloakUser(any())).thenReturn(responseDTO);
+          when(keycloakService.loginUser(anyString(), anyString()))
+              .thenThrow(new BadRequestException(ERROR));
+
+          anonymousUserCreatorService.createAnonymousUser(USER_DTO_SUCHT);
+
+          verifyNoInteractions(rollbackFacade);
+          verifyNoInteractions(rocketChatService);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createAnonymousUser_Should_ThrowInternalServerErrorExceptionAndPerformRollback_When_RocketChatLoginFails()
           throws RocketChatLoginException {
-    KeycloakCreateUserResponseDTO responseDTO =
-        easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
-    when(keycloakService.createKeycloakUser(any())).thenReturn(responseDTO);
-    RocketChatLoginException exception = easyRandom.nextObject(RocketChatLoginException.class);
-    when(rocketChatService.loginUserFirstTime(
-            USER_DTO_SUCHT.getUsername(), USER_DTO_SUCHT.getPassword()))
-        .thenThrow(exception);
-
-    anonymousUserCreatorService.createAnonymousUser(USER_DTO_SUCHT);
-
-    verifyNoInteractions(rollbackFacade);
-    verifyNoInteractions(rocketChatService);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          KeycloakCreateUserResponseDTO responseDTO =
+              easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
+          when(keycloakService.createKeycloakUser(any())).thenReturn(responseDTO);
+          RocketChatLoginException exception =
+              easyRandom.nextObject(RocketChatLoginException.class);
+          when(rocketChatService.loginUserFirstTime(
+                  USER_DTO_SUCHT.getUsername(), USER_DTO_SUCHT.getPassword()))
+              .thenThrow(exception);
+
+          anonymousUserCreatorService.createAnonymousUser(USER_DTO_SUCHT);
+
+          verifyNoInteractions(rollbackFacade);
+          verifyNoInteractions(rocketChatService);
+        });
   }
 
   @Test
-  public void createAnonymousUser_Should_ReturnAnonymousUserCredentials()
-      throws RocketChatLoginException {
+  void createAnonymousUser_Should_ReturnAnonymousUserCredentials() throws RocketChatLoginException {
     KeycloakCreateUserResponseDTO responseDTO =
         easyRandom.nextObject(KeycloakCreateUserResponseDTO.class);
     when(keycloakService.createKeycloakUser(any())).thenReturn(responseDTO);
@@ -118,7 +126,7 @@ public void createAnonymousUser_Should_ReturnAnonymousUserCredentials()
   }
 
   @Test
-  public void
+  void
       createAnonymousUser_Should_throwInternalServerError_When_userToUpdateRocketChatIdDoesNotExist()
           throws RocketChatLoginException {
     KeycloakCreateUserResponseDTO responseDTO =
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/CreateChatV1FacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/CreateChatV1FacadeTest.java
index 1a71be880..578874034 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/CreateChatV1FacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/CreateChatV1FacadeTest.java
@@ -10,7 +10,8 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.RC_GROUP_ID;
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.atLeastOnce;
 import static org.mockito.Mockito.doThrow;
@@ -36,18 +37,18 @@
 import de.caritas.cob.userservice.api.service.agency.AgencyService;
 import java.time.LocalDateTime;
 import java.util.Optional;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InOrder;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.mockito.Spy;
 import org.slf4j.Logger;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class CreateChatV1FacadeTest {
 
   @InjectMocks private CreateChatFacade createChatFacade;
@@ -74,7 +75,7 @@ public class CreateChatV1FacadeTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     when(chat.getId()).thenReturn(CHAT_ID);
     when(chat.getConsultingTypeId()).thenReturn(15);
@@ -83,11 +84,15 @@ public void setup() {
     setInternalState(LogService.class, "LOGGER", logger);
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void createChatV1_Should_ThrowInternalServerErrorException_When_ConsultantHasNoAgency() {
-    createChatFacade.createChatV1(CHAT_DTO, consultant);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          createChatFacade.createChatV1(CHAT_DTO, consultant);
 
-    verify(consultant, atLeastOnce()).getConsultantAgencies();
+          verify(consultant, atLeastOnce()).getConsultantAgencies();
+        });
   }
 
   @Test
@@ -150,124 +155,152 @@ public void createChatV1_Should_SaveChatGroupId() throws RocketChatCreateGroupEx
     inOrder.verify(chatService, times(1)).saveChat(chat);
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV1_Should_ThrowInternalServerErrorExceptionAndDoRollback_When_RocketChatGroupCouldNotBeCreated()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenThrow(new RocketChatCreateGroupException(ERROR));
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-
-    createChatFacade.createChatV1(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, never()).deleteGroupAsSystemUser(Mockito.any());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenThrow(new RocketChatCreateGroupException(ERROR));
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+
+          createChatFacade.createChatV1(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, never()).deleteGroupAsSystemUser(Mockito.any());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV1_Should_ThrowInternalServerErrorExceptionAndRollback_When_RocketChatGroupIsNotPresent()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(GROUP_CHAT_NAME))
-        .thenReturn(Optional.empty());
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-
-    createChatFacade.createChatV1(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, never()).deleteGroupAsSystemUser(Mockito.any());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(GROUP_CHAT_NAME))
+              .thenReturn(Optional.empty());
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+
+          createChatFacade.createChatV1(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, never()).deleteGroupAsSystemUser(Mockito.any());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV1_Should_ThrowInternalServerErrorExceptionAndDoRollback_When_TechnicalUserCouldNotBeAddedToRocketChatGroup()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-    when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
-    when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
-    doThrow(new RocketChatAddUserToGroupException(ERROR))
-        .when(rocketChatService)
-        .addTechnicalUserToGroup(RC_GROUP_ID);
-
-    createChatFacade.createChatV1(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+          when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
+          when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
+          doThrow(new RocketChatAddUserToGroupException(ERROR))
+              .when(rocketChatService)
+              .addTechnicalUserToGroup(RC_GROUP_ID);
+
+          createChatFacade.createChatV1(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV1_Should_ThrowInternalServerErrorExceptionAndDoRollback_When_RocketChatUSerIsNotInitialized()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-    when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
-    when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
-    doThrow(new RocketChatUserNotInitializedException(ERROR))
-        .when(rocketChatService)
-        .addTechnicalUserToGroup(RC_GROUP_ID);
-
-    createChatFacade.createChatV1(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+          when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
+          when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
+          doThrow(new RocketChatUserNotInitializedException(ERROR))
+              .when(rocketChatService)
+              .addTechnicalUserToGroup(RC_GROUP_ID);
+
+          createChatFacade.createChatV1(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV1_Should_ThrowInternalServerErrorExceptionAndDoRollback_When_ChatAgencyRelationCouldNotBeSaved()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any()))
-        .thenThrow(new InternalServerErrorException(""));
-
-    createChatFacade.createChatV1(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any()))
+              .thenThrow(new InternalServerErrorException(""));
+
+          createChatFacade.createChatV1(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV1_Should_ThrowInternalServerErrorExceptionAndDoRollback_When_ChatCouldNotBeSavedWithGroupId()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(chatService.saveChat(Mockito.any()))
-        .thenReturn(chat)
-        .thenThrow(new InternalServerErrorException(""));
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
-    when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-
-    createChatFacade.createChatV1(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(chatService.saveChat(Mockito.any()))
+              .thenReturn(chat)
+              .thenThrow(new InternalServerErrorException(""));
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
+          when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+
+          createChatFacade.createChatV1(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void createChatV1_Should_ThrowInternalServerErrorException_When_ChatCouldNotBeSaved() {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(chatService.saveChat(Mockito.any())).thenThrow(new InternalServerErrorException(""));
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(chatService.saveChat(Mockito.any())).thenThrow(new InternalServerErrorException(""));
 
-    createChatFacade.createChatV1(CHAT_DTO, consultant);
+          createChatFacade.createChatV1(CHAT_DTO, consultant);
 
-    verify(chatService, never()).deleteChat(chat);
-    verify(rocketChatService, never()).deleteGroupAsSystemUser(RC_GROUP_ID);
+          verify(chatService, never()).deleteChat(chat);
+          verify(rocketChatService, never()).deleteGroupAsSystemUser(RC_GROUP_ID);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/CreateChatV2FacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/CreateChatV2FacadeTest.java
index 70ba34b99..7c6e00061 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/CreateChatV2FacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/CreateChatV2FacadeTest.java
@@ -13,6 +13,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.GROUP_CHAT_NAME;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.RC_GROUP_ID;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.never;
@@ -41,9 +42,9 @@
 import java.time.LocalDateTime;
 import java.util.Optional;
 import java.util.UUID;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InOrder;
 import org.mockito.InjectMocks;
@@ -51,9 +52,9 @@
 import org.mockito.Mockito;
 import org.mockito.Spy;
 import org.slf4j.Logger;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class CreateChatV2FacadeTest {
 
   @InjectMocks private CreateChatFacade createChatFacade;
@@ -80,7 +81,7 @@ public class CreateChatV2FacadeTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     when(chat.getId()).thenReturn(CHAT_ID);
     when(chat.getCreateDate()).thenReturn(LocalDateTime.now());
@@ -184,108 +185,132 @@ public void createChatV2_Should_SaveChatGroupId() throws RocketChatCreateGroupEx
     inOrder.verify(chatService, times(1)).saveChat(chat);
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV2_Should_ThrowInternalServerErrorExceptionAndDoRollback_When_RocketChatGroupCouldNotBeCreated()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenThrow(new RocketChatCreateGroupException(ERROR));
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-
-    createChatFacade.createChatV2(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, never()).deleteGroupAsSystemUser(Mockito.any());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenThrow(new RocketChatCreateGroupException(ERROR));
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+
+          createChatFacade.createChatV2(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, never()).deleteGroupAsSystemUser(Mockito.any());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV2_Should_ThrowInternalServerErrorExceptionAndRollback_When_RocketChatGroupIsNotPresent()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(GROUP_CHAT_NAME))
-        .thenReturn(Optional.empty());
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-
-    createChatFacade.createChatV2(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, never()).deleteGroupAsSystemUser(Mockito.any());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(GROUP_CHAT_NAME))
+              .thenReturn(Optional.empty());
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+
+          createChatFacade.createChatV2(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, never()).deleteGroupAsSystemUser(Mockito.any());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV2_Should_ThrowInternalServerErrorExceptionAndDoRollback_When_TechnicalUserCouldNotBeAddedToRocketChatGroup()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-    when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
-    when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
-    doThrow(new RocketChatAddUserToGroupException(ERROR))
-        .when(rocketChatService)
-        .addTechnicalUserToGroup(RC_GROUP_ID);
-
-    createChatFacade.createChatV2(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+          when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
+          when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
+          doThrow(new RocketChatAddUserToGroupException(ERROR))
+              .when(rocketChatService)
+              .addTechnicalUserToGroup(RC_GROUP_ID);
+
+          createChatFacade.createChatV2(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV2_Should_ThrowInternalServerErrorExceptionAndDoRollback_When_RocketChatUserIsNotInitialized()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(chatService.saveChat(Mockito.any())).thenReturn(chat);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-    when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
-    when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
-    doThrow(new RocketChatUserNotInitializedException(ERROR))
-        .when(rocketChatService)
-        .addTechnicalUserToGroup(RC_GROUP_ID);
-
-    createChatFacade.createChatV2(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(chatService.saveChat(Mockito.any())).thenReturn(chat);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+          when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
+          when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
+          doThrow(new RocketChatUserNotInitializedException(ERROR))
+              .when(rocketChatService)
+              .addTechnicalUserToGroup(RC_GROUP_ID);
+
+          createChatFacade.createChatV2(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createChatV2_Should_ThrowInternalServerErrorExceptionAndDoRollback_WhenChatCouldNotBeSavedWithGroupId()
           throws Exception {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(chatService.saveChat(Mockito.any()))
-        .thenReturn(chat)
-        .thenThrow(new InternalServerErrorException(""));
-    when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
-    when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
-    when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
-
-    createChatFacade.createChatV2(CHAT_DTO, consultant);
-
-    verify(chatService, times(1)).deleteChat(chat);
-    verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(chatService.saveChat(Mockito.any()))
+              .thenReturn(chat)
+              .thenThrow(new InternalServerErrorException(""));
+          when(rocketChatService.createPrivateGroupWithSystemUser(Mockito.any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(groupResponseDTO.getGroup()).thenReturn(groupDTO);
+          when(groupDTO.getId()).thenReturn(RC_GROUP_ID);
+          when(chatService.saveChatAgencyRelation(Mockito.any())).thenReturn(chatAgency);
+
+          createChatFacade.createChatV2(CHAT_DTO, consultant);
+
+          verify(chatService, times(1)).deleteChat(chat);
+          verify(rocketChatService, times(1)).deleteGroupAsSystemUser(RC_GROUP_ID);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void createChatV2_Should_ThrowInternalServerErrorException_WhenChatCouldNotBeSaved() {
-    when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
-    when(chatService.saveChat(Mockito.any())).thenThrow(new InternalServerErrorException(""));
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultant.getConsultantAgencies()).thenReturn(CONSULTANT_AGENCIES_SET);
+          when(chatService.saveChat(Mockito.any())).thenThrow(new InternalServerErrorException(""));
 
-    createChatFacade.createChatV2(CHAT_DTO, consultant);
+          createChatFacade.createChatV2(CHAT_DTO, consultant);
 
-    verify(chatService, never()).deleteChat(chat);
-    verify(rocketChatService, never()).deleteGroupAsSystemUser(RC_GROUP_ID);
+          verify(chatService, never()).deleteChat(chat);
+          verify(rocketChatService, never()).deleteGroupAsSystemUser(RC_GROUP_ID);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/CreateEnquiryMessageFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/CreateEnquiryMessageFacadeTest.java
index f03f6c785..a7bab1c37 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/CreateEnquiryMessageFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/CreateEnquiryMessageFacadeTest.java
@@ -31,8 +31,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_INFO_RESPONSE_DTO_2;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.anyLong;
@@ -93,19 +92,21 @@
 import java.util.Optional;
 import javax.servlet.http.HttpServletRequest;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
 import org.slf4j.Logger;
 import org.springframework.web.context.request.RequestContextHolder;
 import org.springframework.web.context.request.ServletRequestAttributes;
 
-@RunWith(MockitoJUnitRunner.class)
-public class CreateEnquiryMessageFacadeTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = org.mockito.quality.Strictness.LENIENT)
+class CreateEnquiryMessageFacadeTest {
 
   private final GroupDTO GROUP_DTO =
       new GroupDTO(
@@ -252,8 +253,8 @@ public class CreateEnquiryMessageFacadeTest {
   private GroupDTO groupDTO;
   private RocketChatCredentials rocketChatCredentials;
 
-  @Before
-  public void setUp() throws NoSuchFieldException, SecurityException {
+  @BeforeEach
+  void setUp() throws NoSuchFieldException, SecurityException {
     setField(
         createEnquiryMessageFacade,
         FIELD_NAME_ROCKET_CHAT_SYSTEM_USER_ID,
@@ -303,7 +304,7 @@ public void setUp() throws NoSuchFieldException, SecurityException {
   }
 
   @Test
-  public void createEnquiryMessage_ShouldNot_ThrowException_When_Successful() throws Exception {
+  void createEnquiryMessage_ShouldNot_ThrowException_When_Successful() throws Exception {
 
     session.setUser(user);
     session.setConsultingTypeId(0);
@@ -357,7 +358,7 @@ public void createEnquiryMessage_ShouldNot_ThrowException_When_Successful() thro
   }
 
   @Test
-  public void createEnquiryMessage_Should_SendDirectEnquiryEmail_When_ConsultantDirectlySet()
+  void createEnquiryMessage_Should_SendDirectEnquiryEmail_When_ConsultantDirectlySet()
       throws Exception {
     session.setUser(user);
     session.setConsultingTypeId(0);
@@ -400,171 +401,198 @@ public void createEnquiryMessage_Should_SendDirectEnquiryEmail_When_ConsultantDi
     resetRequestAttributes();
   }
 
-  @Test(expected = ConflictException.class)
-  public void createEnquiryMessage_Should_ThrowConflictException_When_EnquiryMessageAlreadySaved() {
-
-    when(userHelper.doUsernamesMatch(Mockito.anyString(), Mockito.anyString())).thenReturn(true);
-    when(sessionService.getSession(SESSION_ID))
-        .thenReturn(Optional.of(SESSION_WITH_ENQUIRY_MESSAGE));
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO);
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
-    resetRequestAttributes();
+  @Test
+  void createEnquiryMessage_Should_ThrowConflictException_When_EnquiryMessageAlreadySaved() {
+    assertThrows(
+        ConflictException.class,
+        () -> {
+          when(userHelper.doUsernamesMatch(Mockito.anyString(), Mockito.anyString()))
+              .thenReturn(true);
+          when(sessionService.getSession(SESSION_ID))
+              .thenReturn(Optional.of(SESSION_WITH_ENQUIRY_MESSAGE));
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO);
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = CreateEnquiryMessageException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowCreateEnquiryMessageException_When_SessionNotFoundForUser() {
-
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO);
-    when(userHelper.doUsernamesMatch(Mockito.anyString(), Mockito.anyString())).thenReturn(true);
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.empty());
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
-    resetRequestAttributes();
+    assertThrows(
+        CreateEnquiryMessageException.class,
+        () -> {
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO);
+          when(userHelper.doUsernamesMatch(Mockito.anyString(), Mockito.anyString()))
+              .thenReturn(true);
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.empty());
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = CreateEnquiryMessageException.class)
-  public void
-      createEnquiryMessage_Should_ThrowCreateEnquiryMessageException_When_SessionIsAnonymous() {
-    Session anonymousSession = new EasyRandom().nextObject(Session.class);
-    anonymousSession.setRegistrationType(ANONYMOUS);
-    anonymousSession.getUser().setUserId(USER.getUserId());
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO);
-    when(userHelper.doUsernamesMatch(Mockito.anyString(), Mockito.anyString())).thenReturn(true);
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(anonymousSession));
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
-    resetRequestAttributes();
+  @Test
+  void createEnquiryMessage_Should_ThrowCreateEnquiryMessageException_When_SessionIsAnonymous() {
+    assertThrows(
+        CreateEnquiryMessageException.class,
+        () -> {
+          Session anonymousSession = new EasyRandom().nextObject(Session.class);
+          anonymousSession.setRegistrationType(ANONYMOUS);
+          anonymousSession.getUser().setUserId(USER.getUserId());
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO);
+          when(userHelper.doUsernamesMatch(Mockito.anyString(), Mockito.anyString()))
+              .thenReturn(true);
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(anonymousSession));
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
-      createEnquiryMessage_Should_ThrowInternalServerErrorException_When_GetSessionCallFails() {
-
-    when(userHelper.doUsernamesMatch(Mockito.anyString(), Mockito.anyString())).thenReturn(true);
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO);
-    when(sessionService.getSession(SESSION_ID))
-        .thenThrow(new InternalServerErrorException(MESSAGE))
-        .thenReturn(Optional.of(SESSION_WITHOUT_CONSULTANT));
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
-    resetRequestAttributes();
+  @Test
+  void createEnquiryMessage_Should_ThrowInternalServerErrorException_When_GetSessionCallFails() {
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(userHelper.doUsernamesMatch(Mockito.anyString(), Mockito.anyString()))
+              .thenReturn(true);
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO);
+          when(sessionService.getSession(SESSION_ID))
+              .thenThrow(new InternalServerErrorException(MESSAGE))
+              .thenReturn(Optional.of(SESSION_WITHOUT_CONSULTANT));
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowInternalServerErrorException_When_CreationOfRocketChatGroupFailsWithAnException()
           throws RocketChatCreateGroupException {
-
-    session.setUser(user);
-    session.setConsultingTypeId(0);
-    session.setConsultant(null);
-    session.setEnquiryMessageDate(null);
-    rocketChatUserDTO.setUsername(USERNAME);
-    userInfoResponseDTO.setUser(rocketChatUserDTO);
-    rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
-    rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
-
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
-    when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
-    when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
-        .thenReturn(session.getId().toString());
-    when(rocketChatService.createPrivateGroup(anyString(), any()))
-        .thenThrow(new RocketChatCreateGroupException(ERROR));
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
-    resetRequestAttributes();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          session.setUser(user);
+          session.setConsultingTypeId(0);
+          session.setConsultant(null);
+          session.setEnquiryMessageDate(null);
+          rocketChatUserDTO.setUsername(USERNAME);
+          userInfoResponseDTO.setUser(rocketChatUserDTO);
+          rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
+          rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
+
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
+          when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
+          when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
+              .thenReturn(session.getId().toString());
+          when(rocketChatService.createPrivateGroup(anyString(), any()))
+              .thenThrow(new RocketChatCreateGroupException(ERROR));
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowInternalServerErrorException_When_PostMessageFailsWithAnException() {
-
-    session.setUser(user);
-    session.setConsultingTypeId(0);
-    session.setConsultant(null);
-    session.setEnquiryMessageDate(null);
-    rocketChatUserDTO.setUsername(USERNAME);
-    userInfoResponseDTO.setUser(rocketChatUserDTO);
-    groupDTO.setId(RC_GROUP_ID);
-    groupResponseDTO.setSuccess(true);
-    groupResponseDTO.setGroup(groupDTO);
-    rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
-    rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
-
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
-    when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
-        .thenReturn(extendedConsultingTypeResponseDTO);
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
-    when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
-    resetRequestAttributes();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          session.setUser(user);
+          session.setConsultingTypeId(0);
+          session.setConsultant(null);
+          session.setEnquiryMessageDate(null);
+          rocketChatUserDTO.setUsername(USERNAME);
+          userInfoResponseDTO.setUser(rocketChatUserDTO);
+          groupDTO.setId(RC_GROUP_ID);
+          groupResponseDTO.setSuccess(true);
+          groupResponseDTO.setGroup(groupDTO);
+          rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
+          rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
+
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
+          when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
+              .thenReturn(extendedConsultingTypeResponseDTO);
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
+          when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowInternalServerErrorException_When_ConsultantsOfAgencyCanNotBeReadFromDB() {
-
-    session.setUser(user);
-    session.setConsultingTypeId(0);
-    session.setConsultant(null);
-    rocketChatUserDTO.setUsername(USERNAME);
-    userInfoResponseDTO.setUser(rocketChatUserDTO);
-    rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
-    rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
-
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
-    when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
-    verify(rocketChatService, atLeast(1)).rollbackGroup(RC_GROUP_ID, rocketChatCredentials);
-    resetRequestAttributes();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          session.setUser(user);
+          session.setConsultingTypeId(0);
+          session.setConsultant(null);
+          rocketChatUserDTO.setUsername(USERNAME);
+          userInfoResponseDTO.setUser(rocketChatUserDTO);
+          rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
+          rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
+
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
+          when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
+          verify(rocketChatService, atLeast(1)).rollbackGroup(RC_GROUP_ID, rocketChatCredentials);
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowInternalServerErrorException_When_AddConsultantToRocketChatGroupFails()
           throws Exception {
-
-    session.setUser(user);
-    session.setConsultingTypeId(0);
-    session.setConsultant(null);
-    session.setEnquiryMessageDate(null);
-    rocketChatUserDTO.setUsername(USERNAME);
-    userInfoResponseDTO.setUser(rocketChatUserDTO);
-    groupDTO.setId(RC_GROUP_ID);
-    groupResponseDTO.setSuccess(true);
-    groupResponseDTO.setGroup(groupDTO);
-    rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
-    rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
-
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
-    when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
-    when(rocketChatService.createPrivateGroup(anyString(), any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
-        .thenReturn(session.getId().toString());
-
-    Mockito.doThrow(new RocketChatAddUserToGroupException(MESSAGE))
-        .when(rocketChatService)
-        .addUserToGroup(anyString(), anyString());
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
-    resetRequestAttributes();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          session.setUser(user);
+          session.setConsultingTypeId(0);
+          session.setConsultant(null);
+          session.setEnquiryMessageDate(null);
+          rocketChatUserDTO.setUsername(USERNAME);
+          userInfoResponseDTO.setUser(rocketChatUserDTO);
+          groupDTO.setId(RC_GROUP_ID);
+          groupResponseDTO.setSuccess(true);
+          groupResponseDTO.setGroup(groupDTO);
+          rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
+          rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
+
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
+          when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
+          when(rocketChatService.createPrivateGroup(anyString(), any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
+              .thenReturn(session.getId().toString());
+
+          Mockito.doThrow(new RocketChatAddUserToGroupException(MESSAGE))
+              .when(rocketChatService)
+              .addUserToGroup(anyString(), anyString());
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
+          resetRequestAttributes();
+        });
   }
 
   @Test
-  public void createEnquiryMessage_Should_DeleteRcGroup_When_PostMessageFails() throws Exception {
+  void createEnquiryMessage_Should_DeleteRcGroup_When_PostMessageFails() throws Exception {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(SESSION_WITHOUT_CONSULTANT));
     when(consultingTypeManager.getConsultingTypeSettings(
@@ -593,7 +621,7 @@ public void createEnquiryMessage_Should_DeleteRcGroup_When_PostMessageFails() th
   }
 
   @Test
-  public void createEnquiryMessage_Should_DeleteRcGroup_When_AddConsultantToRocketChatGroupFails()
+  void createEnquiryMessage_Should_DeleteRcGroup_When_AddConsultantToRocketChatGroupFails()
       throws Exception {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(SESSION_WITHOUT_CONSULTANT));
@@ -623,19 +651,22 @@ public void createEnquiryMessage_Should_DeleteRcGroup_When_AddConsultantToRocket
     resetRequestAttributes();
   }
 
-  @Test(expected = CreateEnquiryMessageException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowCreateEnquiryMessageException_When_KeycloakAndRocketChatUsersDontMatch() {
-
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO_2);
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
-    resetRequestAttributes();
+    assertThrows(
+        CreateEnquiryMessageException.class,
+        () -> {
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(USER_INFO_RESPONSE_DTO_2);
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(USER, SESSION_ID, MESSAGE, null, RC_CREDENTIALS));
+          resetRequestAttributes();
+        });
   }
 
   @Test
-  public void createEnquiryMessage_Should_UpdateCorrectSessionInformation_When_Successful()
+  void createEnquiryMessage_Should_UpdateCorrectSessionInformation_When_Successful()
       throws Exception {
 
     session.setUser(user);
@@ -678,138 +709,150 @@ public void createEnquiryMessage_Should_UpdateCorrectSessionInformation_When_Suc
     resetRequestAttributes();
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowInternalServerErrorException_When_CreatePrivateGroupWithSystemUserFails()
           throws RocketChatCreateGroupException {
-
-    session.setUser(user);
-    session.setConsultingTypeId(0);
-    session.setConsultant(null);
-    extendedConsultingTypeResponseDTO.setInitializeFeedbackChat(true);
-    rocketChatUserDTO.setUsername(USERNAME);
-    userInfoResponseDTO.setUser(rocketChatUserDTO);
-    groupDTO.setId(RC_GROUP_ID);
-    groupResponseDTO.setSuccess(true);
-    groupResponseDTO.setGroup(groupDTO);
-    rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
-    rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
-
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
-    when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
-        .thenReturn(extendedConsultingTypeResponseDTO);
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
-    when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
-    when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
-        .thenReturn(session.getId().toString());
-    when(rocketChatService.createPrivateGroup(anyString(), any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
-    resetRequestAttributes();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          session.setUser(user);
+          session.setConsultingTypeId(0);
+          session.setConsultant(null);
+          extendedConsultingTypeResponseDTO.setInitializeFeedbackChat(true);
+          rocketChatUserDTO.setUsername(USERNAME);
+          userInfoResponseDTO.setUser(rocketChatUserDTO);
+          groupDTO.setId(RC_GROUP_ID);
+          groupResponseDTO.setSuccess(true);
+          groupResponseDTO.setGroup(groupDTO);
+          rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
+          rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
+
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
+          when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
+              .thenReturn(extendedConsultingTypeResponseDTO);
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
+          when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
+          when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
+              .thenReturn(session.getId().toString());
+          when(rocketChatService.createPrivateGroup(anyString(), any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowInternalServerErrorException_When_UpdateRocketChatIdForUserFails()
           throws RocketChatCreateGroupException {
-
-    session.setUser(user);
-    session.setConsultingTypeId(0);
-    session.setConsultant(null);
-    rocketChatUserDTO.setUsername(USERNAME);
-    userInfoResponseDTO.setUser(rocketChatUserDTO);
-    groupDTO.setId(RC_GROUP_ID);
-    groupResponseDTO.setSuccess(true);
-    groupResponseDTO.setGroup(groupDTO);
-    rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
-    rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
-    extendedConsultingTypeResponseDTO.setInitializeFeedbackChat(true);
-
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
-    when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
-        .thenReturn(extendedConsultingTypeResponseDTO);
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
-    when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
-    when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
-        .thenReturn(session.getId().toString());
-    when(rocketChatService.createPrivateGroup(anyString(), any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
-    resetRequestAttributes();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          session.setUser(user);
+          session.setConsultingTypeId(0);
+          session.setConsultant(null);
+          rocketChatUserDTO.setUsername(USERNAME);
+          userInfoResponseDTO.setUser(rocketChatUserDTO);
+          groupDTO.setId(RC_GROUP_ID);
+          groupResponseDTO.setSuccess(true);
+          groupResponseDTO.setGroup(groupDTO);
+          rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
+          rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
+          extendedConsultingTypeResponseDTO.setInitializeFeedbackChat(true);
+
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
+          when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
+              .thenReturn(extendedConsultingTypeResponseDTO);
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
+          when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
+          when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
+              .thenReturn(session.getId().toString());
+          when(rocketChatService.createPrivateGroup(anyString(), any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
-      createEnquiryMessage_Should_ThrowInternalServerErrorException_When_UpdateOfSessionFails()
-          throws RocketChatCreateGroupException {
-
-    session.setUser(user);
-    session.setConsultingTypeId(0);
-    session.setConsultant(null);
-    rocketChatUserDTO.setUsername(USERNAME);
-    userInfoResponseDTO.setUser(rocketChatUserDTO);
-    groupDTO.setId(RC_GROUP_ID);
-    groupResponseDTO.setSuccess(true);
-    groupResponseDTO.setGroup(groupDTO);
-    rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
-    rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
-    extendedConsultingTypeResponseDTO.setInitializeFeedbackChat(true);
-    InternalServerErrorException internalServerErrorException =
-        new InternalServerErrorException(MESSAGE);
-
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
-    when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
-        .thenReturn(extendedConsultingTypeResponseDTO);
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
-    when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
-    when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
-        .thenReturn(session.getId().toString());
-    when(rocketChatService.createPrivateGroup(Mockito.anyString(), any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
-    resetRequestAttributes();
+  @Test
+  void createEnquiryMessage_Should_ThrowInternalServerErrorException_When_UpdateOfSessionFails()
+      throws RocketChatCreateGroupException {
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          session.setUser(user);
+          session.setConsultingTypeId(0);
+          session.setConsultant(null);
+          rocketChatUserDTO.setUsername(USERNAME);
+          userInfoResponseDTO.setUser(rocketChatUserDTO);
+          groupDTO.setId(RC_GROUP_ID);
+          groupResponseDTO.setSuccess(true);
+          groupResponseDTO.setGroup(groupDTO);
+          rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
+          rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
+          extendedConsultingTypeResponseDTO.setInitializeFeedbackChat(true);
+          InternalServerErrorException internalServerErrorException =
+              new InternalServerErrorException(MESSAGE);
+
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
+          when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
+              .thenReturn(extendedConsultingTypeResponseDTO);
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
+          when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
+          when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
+              .thenReturn(session.getId().toString());
+          when(rocketChatService.createPrivateGroup(Mockito.anyString(), any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
+          resetRequestAttributes();
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createEnquiryMessage_Should_ThrowInternalServerErrorException_When_PrivateGroupWithSystemUserIsNotPresent()
           throws RocketChatCreateGroupException {
-
-    session.setUser(user);
-    session.setConsultingTypeId(0);
-    session.setConsultant(null);
-    extendedConsultingTypeResponseDTO.setInitializeFeedbackChat(true);
-    rocketChatUserDTO.setUsername(USERNAME);
-    userInfoResponseDTO.setUser(rocketChatUserDTO);
-    groupDTO.setId(RC_GROUP_ID);
-    groupResponseDTO.setSuccess(true);
-    groupResponseDTO.setGroup(groupDTO);
-    rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
-    rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
-
-    when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
-    when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
-        .thenReturn(extendedConsultingTypeResponseDTO);
-    when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
-    when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
-    when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
-        .thenReturn(session.getId().toString());
-    when(rocketChatService.createPrivateGroup(anyString(), any()))
-        .thenReturn(Optional.of(groupResponseDTO));
-    when(rocketChatService.createPrivateGroupWithSystemUser(any())).thenReturn(Optional.empty());
-
-    createEnquiryMessageFacade.createEnquiryMessage(
-        new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
-    resetRequestAttributes();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          session.setUser(user);
+          session.setConsultingTypeId(0);
+          session.setConsultant(null);
+          extendedConsultingTypeResponseDTO.setInitializeFeedbackChat(true);
+          rocketChatUserDTO.setUsername(USERNAME);
+          userInfoResponseDTO.setUser(rocketChatUserDTO);
+          groupDTO.setId(RC_GROUP_ID);
+          groupResponseDTO.setSuccess(true);
+          groupResponseDTO.setGroup(groupDTO);
+          rocketChatCredentials.setRocketChatUserId(RC_USER_ID);
+          rocketChatCredentials.setRocketChatUsername(RC_USERNAME);
+
+          when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(session));
+          when(consultingTypeManager.getConsultingTypeSettings(session.getConsultingTypeId()))
+              .thenReturn(extendedConsultingTypeResponseDTO);
+          when(rocketChatService.getUserInfo(RC_USER_ID)).thenReturn(userInfoResponseDTO);
+          when(userHelper.doUsernamesMatch(anyString(), anyString())).thenReturn(true);
+          when(rocketChatRoomNameGenerator.generateGroupName(any(Session.class)))
+              .thenReturn(session.getId().toString());
+          when(rocketChatService.createPrivateGroup(anyString(), any()))
+              .thenReturn(Optional.of(groupResponseDTO));
+          when(rocketChatService.createPrivateGroupWithSystemUser(any()))
+              .thenReturn(Optional.empty());
+
+          createEnquiryMessageFacade.createEnquiryMessage(
+              new EnquiryData(user, SESSION_ID, MESSAGE, null, rocketChatCredentials));
+          resetRequestAttributes();
+        });
   }
 
   @Test
-  public void createEnquiryMessage_Should_DeleteRcGroup_WhenAddSystemUserToGroupFails() {
+  void createEnquiryMessage_Should_DeleteRcGroup_WhenAddSystemUserToGroupFails() {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(SESSION_WITHOUT_CONSULTANT));
     when(consultingTypeManager.getConsultingTypeSettings(
@@ -831,7 +874,7 @@ public void createEnquiryMessage_Should_DeleteRcGroup_WhenAddSystemUserToGroupFa
   }
 
   @Test
-  public void createEnquiryMessage_Should_DeleteRcGroup_WhenRemoveSystemMessagesFails()
+  void createEnquiryMessage_Should_DeleteRcGroup_WhenRemoveSystemMessagesFails()
       throws RocketChatCreateGroupException, RocketChatRemoveSystemMessagesException,
           RocketChatUserNotInitializedException {
 
@@ -863,7 +906,7 @@ public void createEnquiryMessage_Should_DeleteRcGroup_WhenRemoveSystemMessagesFa
   }
 
   @Test
-  public void
+  void
       createEnquiryMessage_Should_DeleteRcGroupAndFeedbackGroup_WhenAddSystemUserToFeedbackGroupFails() {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(SESSION_WITHOUT_CONSULTANT));
@@ -890,7 +933,7 @@ public void createEnquiryMessage_Should_DeleteRcGroup_WhenRemoveSystemMessagesFa
   }
 
   @Test
-  public void
+  void
       createEnquiryMessage_Should_DeleteRcGroupAndFeedbackGroup_When_WhenRemoveSystemMessagesFailsForFeedbackGroup()
           throws Exception {
 
@@ -930,7 +973,7 @@ public void createEnquiryMessage_Should_DeleteRcGroup_WhenRemoveSystemMessagesFa
   }
 
   @Test
-  public void
+  void
       createEnquiryMessage_Should_DeleteRcGroupAndFeedbackGroup_When_AddConsultantToRocketChatFeedbackGroupFails()
           throws RocketChatCreateGroupException, RocketChatAddUserToGroupException {
 
@@ -969,7 +1012,7 @@ public void createEnquiryMessage_Should_DeleteRcGroup_WhenRemoveSystemMessagesFa
   }
 
   @Test
-  public void createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_UpdateOfSessionFails()
+  void createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_UpdateOfSessionFails()
       throws Exception {
 
     Session spySession = Mockito.spy(SESSION_WITHOUT_CONSULTANT);
@@ -1003,7 +1046,7 @@ public void createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_UpdateOf
   }
 
   @Test
-  public void
+  void
       createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_PostWelcomeMessageFailsWithAnException()
           throws Exception {
 
@@ -1048,9 +1091,8 @@ public void createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_UpdateOf
   }
 
   @Test
-  public void
-      createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_PostMessageFailsWithAnException()
-          throws Exception {
+  void createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_PostMessageFailsWithAnException()
+      throws Exception {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(SESSION_WITHOUT_CONSULTANT));
     when(consultingTypeManager.getConsultingTypeSettings(
@@ -1092,9 +1134,8 @@ public void createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_UpdateOf
   }
 
   @Test
-  public void
-      createEnquiryMessage_Should_DeleteRcGroupFeedback_When_UpdateOfUserFailsWithAnException()
-          throws Exception {
+  void createEnquiryMessage_Should_DeleteRcGroupFeedback_When_UpdateOfUserFailsWithAnException()
+      throws Exception {
 
     when(sessionService.getSession(SESSION_ID)).thenReturn(Optional.of(SESSION_WITHOUT_CONSULTANT));
     when(consultingTypeManager.getConsultingTypeSettings(
@@ -1127,7 +1168,7 @@ public void createEnquiryMessage_Should_DeleteRcGroupFeedbackGroup_When_UpdateOf
   }
 
   @Test
-  public void createEnquiryMessage_Should_PostAliasOnlyMessageAndWelcomeMessage() throws Exception {
+  void createEnquiryMessage_Should_PostAliasOnlyMessageAndWelcomeMessage() throws Exception {
 
     session.setUser(user);
     session.setConsultingTypeId(0);
@@ -1174,7 +1215,7 @@ public void createEnquiryMessage_Should_PostAliasOnlyMessageAndWelcomeMessage()
   }
 
   @Test
-  public void createEnquiryMessage_Should_setSessionInProgress_When_consultantIsAlreadyAssigned()
+  void createEnquiryMessage_Should_setSessionInProgress_When_consultantIsAlreadyAssigned()
       throws Exception {
     var session = mock(Session.class);
     when(session.getUser()).thenReturn(user);
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/CreateNewConsultingTypeFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/CreateNewConsultingTypeFacadeTest.java
index ceacf749f..df59478bf 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/CreateNewConsultingTypeFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/CreateNewConsultingTypeFacadeTest.java
@@ -8,8 +8,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.UNKNOWN_CONSULTING_TYPE_ID;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
@@ -27,13 +26,13 @@
 import de.caritas.cob.userservice.api.service.statistics.StatisticsService;
 import de.caritas.cob.userservice.consultingtypeservice.generated.web.model.ExtendedConsultingTypeResponseDTO;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class CreateNewConsultingTypeFacadeTest {
 
   @InjectMocks private CreateNewConsultingTypeFacade createNewConsultingTypeFacade;
@@ -111,38 +110,48 @@ public class CreateNewConsultingTypeFacadeTest {
         .initializeUserChatAgencyRelation(any(), any(), any());
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       initializeNewConsultingType_Should_ThrowBadRequestException_When_ProvidedWithInvalidConsultingType_For_NewConsultingTypeRegistrations() {
-    EasyRandom easyRandom = new EasyRandom();
-    UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
-    userDTO.setConsultingType(INVALID_CONSULTING_TYPE_ID);
-    User user = easyRandom.nextObject(User.class);
-    RocketChatCredentials rocketChatCredentials =
-        easyRandom.nextObject(RocketChatCredentials.class);
-    when(consultingTypeManager.getConsultingTypeSettings(INVALID_CONSULTING_TYPE_ID))
-        .thenThrow(new NumberFormatException(""));
-    createNewConsultingTypeFacade.initializeNewConsultingType(userDTO, user, rocketChatCredentials);
-
-    verify(createUserChatRelationFacade, times(0))
-        .initializeUserChatAgencyRelation(any(), any(), any());
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          EasyRandom easyRandom = new EasyRandom();
+          UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
+          userDTO.setConsultingType(INVALID_CONSULTING_TYPE_ID);
+          User user = easyRandom.nextObject(User.class);
+          RocketChatCredentials rocketChatCredentials =
+              easyRandom.nextObject(RocketChatCredentials.class);
+          when(consultingTypeManager.getConsultingTypeSettings(INVALID_CONSULTING_TYPE_ID))
+              .thenThrow(new NumberFormatException(""));
+          createNewConsultingTypeFacade.initializeNewConsultingType(
+              userDTO, user, rocketChatCredentials);
+
+          verify(createUserChatRelationFacade, times(0))
+              .initializeUserChatAgencyRelation(any(), any(), any());
+        });
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       initializeNewConsultingType_Should_ThrowBadRequestException_When_ProvidedWithUnknownConsultingType_For_NewConsultingTypeRegistrations() {
-    EasyRandom easyRandom = new EasyRandom();
-    UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
-    userDTO.setConsultingType(UNKNOWN_CONSULTING_TYPE_ID);
-    User user = easyRandom.nextObject(User.class);
-    RocketChatCredentials rocketChatCredentials =
-        easyRandom.nextObject(RocketChatCredentials.class);
-    when(consultingTypeManager.getConsultingTypeSettings(UNKNOWN_CONSULTING_TYPE_ID))
-        .thenThrow(new MissingConsultingTypeException(""));
-    createNewConsultingTypeFacade.initializeNewConsultingType(userDTO, user, rocketChatCredentials);
-
-    verify(createUserChatRelationFacade, times(0))
-        .initializeUserChatAgencyRelation(any(), any(), any());
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          EasyRandom easyRandom = new EasyRandom();
+          UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
+          userDTO.setConsultingType(UNKNOWN_CONSULTING_TYPE_ID);
+          User user = easyRandom.nextObject(User.class);
+          RocketChatCredentials rocketChatCredentials =
+              easyRandom.nextObject(RocketChatCredentials.class);
+          when(consultingTypeManager.getConsultingTypeSettings(UNKNOWN_CONSULTING_TYPE_ID))
+              .thenThrow(new MissingConsultingTypeException(""));
+          createNewConsultingTypeFacade.initializeNewConsultingType(
+              userDTO, user, rocketChatCredentials);
+
+          verify(createUserChatRelationFacade, times(0))
+              .initializeUserChatAgencyRelation(any(), any(), any());
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/CreateSessionFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/CreateSessionFacadeTest.java
index 88b896b25..1c1df7e50 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/CreateSessionFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/CreateSessionFacadeTest.java
@@ -13,7 +13,8 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_SESSION_RESPONSE_DTO_LIST_U25;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyBoolean;
 import static org.mockito.ArgumentMatchers.anyInt;
@@ -42,16 +43,16 @@
 import de.caritas.cob.userservice.consultingtypeservice.generated.web.model.ExtendedConsultingTypeResponseDTO;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.slf4j.Logger;
 import org.springframework.http.HttpStatus;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class CreateSessionFacadeTest {
 
   @InjectMocks private CreateSessionFacade createSessionFacade;
@@ -62,67 +63,83 @@ public class CreateSessionFacadeTest {
   @Mock private UserAccountService userAccountProvider;
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(LogService.class, "LOGGER", logger);
   }
 
   /** Method: createUserSession */
-  @Test(expected = ConflictException.class)
+  @Test
   public void createUserSession_Should_ReturnConflict_When_AlreadyRegisteredToConsultingType() {
-
-    when(sessionService.getSessionsForUserByConsultingTypeId(any(), anyInt()))
-        .thenReturn(SESSION_LIST);
-    createSessionFacade.createUserSession(USER_DTO_SUCHT, USER, CONSULTING_TYPE_SETTINGS_SUCHT);
-
-    verify(sessionService, times(0)).saveSession(any());
+    assertThrows(
+        ConflictException.class,
+        () -> {
+          when(sessionService.getSessionsForUserByConsultingTypeId(any(), anyInt()))
+              .thenReturn(SESSION_LIST);
+          createSessionFacade.createUserSession(
+              USER_DTO_SUCHT, USER, CONSULTING_TYPE_SETTINGS_SUCHT);
+
+          verify(sessionService, times(0)).saveSession(any());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createUserSession_Should_ReturnInternalServerErrorAndRollbackUserAccount_When_SessionCouldNotBeSaved() {
-
-    when(sessionService.getSessionsForUserId(USER_ID))
-        .thenReturn(USER_SESSION_RESPONSE_DTO_LIST_U25);
-    when(agencyVerifier.getVerifiedAgency(AGENCY_ID, 0)).thenReturn(AGENCY_DTO_U25);
-    when(sessionService.initializeSession(any(), any(), any(Boolean.class)))
-        .thenThrow(new InternalServerErrorException(MESSAGE));
-
-    createSessionFacade.createUserSession(USER_DTO_SUCHT, USER, CONSULTING_TYPE_SETTINGS_SUCHT);
-
-    verify(logger, atLeastOnce()).error(anyString(), anyString(), anyString());
-    verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(sessionService.getSessionsForUserId(USER_ID))
+              .thenReturn(USER_SESSION_RESPONSE_DTO_LIST_U25);
+          when(agencyVerifier.getVerifiedAgency(AGENCY_ID, 0)).thenReturn(AGENCY_DTO_U25);
+          when(sessionService.initializeSession(any(), any(), any(Boolean.class)))
+              .thenThrow(new InternalServerErrorException(MESSAGE));
+
+          createSessionFacade.createUserSession(
+              USER_DTO_SUCHT, USER, CONSULTING_TYPE_SETTINGS_SUCHT);
+
+          verify(logger, atLeastOnce()).error(anyString(), anyString(), anyString());
+          verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createUserSession_Should_ReturnInternalServerErrorAndRollbackUserAccount_When_SessionDataCouldNotBeSaved() {
-
-    when(sessionService.getSessionsForUserId(USER_ID))
-        .thenReturn(USER_SESSION_RESPONSE_DTO_LIST_U25);
-    when(agencyVerifier.getVerifiedAgency(AGENCY_ID, 0)).thenReturn(AGENCY_DTO_U25);
-    when(sessionService.initializeSession(any(), any(), any(Boolean.class)))
-        .thenThrow(new InternalServerErrorException(MESSAGE));
-    doThrow(INTERNAL_SERVER_ERROR_EXCEPTION)
-        .when(sessionDataService)
-        .saveSessionData(any(Session.class), any());
-
-    createSessionFacade.createUserSession(USER_DTO_SUCHT, USER, CONSULTING_TYPE_SETTINGS_SUCHT);
-
-    verify(logger, atLeastOnce()).error(anyString(), anyString(), anyString());
-    verify(sessionService, times(1)).deleteSession(any());
-    verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(sessionService.getSessionsForUserId(USER_ID))
+              .thenReturn(USER_SESSION_RESPONSE_DTO_LIST_U25);
+          when(agencyVerifier.getVerifiedAgency(AGENCY_ID, 0)).thenReturn(AGENCY_DTO_U25);
+          when(sessionService.initializeSession(any(), any(), any(Boolean.class)))
+              .thenThrow(new InternalServerErrorException(MESSAGE));
+          doThrow(INTERNAL_SERVER_ERROR_EXCEPTION)
+              .when(sessionDataService)
+              .saveSessionData(any(Session.class), any());
+
+          createSessionFacade.createUserSession(
+              USER_DTO_SUCHT, USER, CONSULTING_TYPE_SETTINGS_SUCHT);
+
+          verify(logger, atLeastOnce()).error(anyString(), anyString(), anyString());
+          verify(sessionService, times(1)).deleteSession(any());
+          verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+        });
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       createUserSession_Should_ReturnBadRequest_When_AgencyForConsultingTypeCouldNotBeFound() {
-
-    when(sessionService.getSessionsForUserId(USER_ID))
-        .thenReturn(USER_SESSION_RESPONSE_DTO_LIST_U25);
-    when(agencyVerifier.getVerifiedAgency(AGENCY_ID, 0)).thenReturn(null);
-
-    createSessionFacade.createUserSession(USER_DTO_SUCHT, USER, CONSULTING_TYPE_SETTINGS_SUCHT);
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          when(sessionService.getSessionsForUserId(USER_ID))
+              .thenReturn(USER_SESSION_RESPONSE_DTO_LIST_U25);
+          when(agencyVerifier.getVerifiedAgency(AGENCY_ID, 0)).thenReturn(null);
+
+          createSessionFacade.createUserSession(
+              USER_DTO_SUCHT, USER, CONSULTING_TYPE_SETTINGS_SUCHT);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/CreateUserChatRelationFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/CreateUserChatRelationFacadeTest.java
index e0081d1d0..1f6dce75d 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/CreateUserChatRelationFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/CreateUserChatRelationFacadeTest.java
@@ -7,8 +7,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_WITH_RC_ID;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -30,15 +29,15 @@
 import java.util.Collections;
 import java.util.List;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.data.auditing.AuditingHandler;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class CreateUserChatRelationFacadeTest {
 
   @InjectMocks private CreateUserChatRelationFacade createUserChatRelationFacade;
@@ -126,46 +125,54 @@ public class CreateUserChatRelationFacadeTest {
     assertEquals(rocketChatCredentials.getRocketChatUserId(), captor.getValue().getRcUserId());
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       initializeUserChatAgencyRelation_Should_ThrowInternalServerErrorExceptionAndRollBackUserAccount_IfLoginToRocketChatFails_OnUpdatingRocketChatCredentialsInDb()
           throws RocketChatLoginException {
-    EasyRandom easyRandom = new EasyRandom();
-    UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
-    User user = easyRandom.nextObject(User.class);
-    user.setRcUserId(null);
-    ArgumentCaptor<RollbackUserAccountInformation> captor =
-        ArgumentCaptor.forClass(RollbackUserAccountInformation.class);
-
-    when(rocketChatService.loginUserFirstTime(any(), any()))
-        .thenThrow(new RocketChatLoginException(MESSAGE));
-
-    createUserChatRelationFacade.initializeUserChatAgencyRelation(userDTO, user, null);
-
-    verify(rollbackFacade).rollBackUserAccount(captor.capture());
-    assertEquals(user, captor.getValue().getUser());
-    assertTrue(captor.getValue().isRollBackUserAccount());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          EasyRandom easyRandom = new EasyRandom();
+          UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
+          User user = easyRandom.nextObject(User.class);
+          user.setRcUserId(null);
+          ArgumentCaptor<RollbackUserAccountInformation> captor =
+              ArgumentCaptor.forClass(RollbackUserAccountInformation.class);
+
+          when(rocketChatService.loginUserFirstTime(any(), any()))
+              .thenThrow(new RocketChatLoginException(MESSAGE));
+
+          createUserChatRelationFacade.initializeUserChatAgencyRelation(userDTO, user, null);
+
+          verify(rollbackFacade).rollBackUserAccount(captor.capture());
+          assertEquals(user, captor.getValue().getUser());
+          assertTrue(captor.getValue().isRollBackUserAccount());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       initializeUserChatAgencyRelation_Should_ThrowInternalServerErrorExceptionAndRollBackUserAccount_IfLoginToRocketChatReturnsInvalidResponse_OnUpdatingRocketChatCredentialsInDb()
           throws RocketChatLoginException {
-    EasyRandom easyRandom = new EasyRandom();
-    UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
-    User user = easyRandom.nextObject(User.class);
-    user.setRcUserId(null);
-    ArgumentCaptor<RollbackUserAccountInformation> captor =
-        ArgumentCaptor.forClass(RollbackUserAccountInformation.class);
-
-    when(rocketChatService.loginUserFirstTime(any(), any()))
-        .thenReturn(LOGIN_RESPONSE_ENTITY_OK_NO_TOKEN);
-
-    createUserChatRelationFacade.initializeUserChatAgencyRelation(userDTO, user, null);
-
-    verify(rollbackFacade).rollBackUserAccount(captor.capture());
-    assertEquals(user, captor.getValue().getUser());
-    assertTrue(captor.getValue().isRollBackUserAccount());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          EasyRandom easyRandom = new EasyRandom();
+          UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
+          User user = easyRandom.nextObject(User.class);
+          user.setRcUserId(null);
+          ArgumentCaptor<RollbackUserAccountInformation> captor =
+              ArgumentCaptor.forClass(RollbackUserAccountInformation.class);
+
+          when(rocketChatService.loginUserFirstTime(any(), any()))
+              .thenReturn(LOGIN_RESPONSE_ENTITY_OK_NO_TOKEN);
+
+          createUserChatRelationFacade.initializeUserChatAgencyRelation(userDTO, user, null);
+
+          verify(rollbackFacade).rollBackUserAccount(captor.capture());
+          assertEquals(user, captor.getValue().getUser());
+          assertTrue(captor.getValue().isRollBackUserAccount());
+        });
   }
 
   @Test
@@ -193,45 +200,53 @@ public class CreateUserChatRelationFacadeTest {
     assertEquals(user, captor.getValue().getUser());
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       initializeUserChatAgencyRelation_Should_ThrowInternalServerErrorExceptionAndRollBackUserAccount_IfCreateUserChatAgencyRelationFails() {
-    ArgumentCaptor<RollbackUserAccountInformation> captor =
-        ArgumentCaptor.forClass(RollbackUserAccountInformation.class);
-    EasyRandom easyRandom = new EasyRandom();
-    UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
-    User user = easyRandom.nextObject(User.class);
-    RocketChatCredentials rocketChatCredentials =
-        easyRandom.nextObject(RocketChatCredentials.class);
-
-    when(userAgencyService.saveUserAgency(any()))
-        .thenThrow(new InternalServerErrorException(MESSAGE));
-
-    createUserChatRelationFacade.initializeUserChatAgencyRelation(
-        userDTO, user, rocketChatCredentials);
-
-    verify(rollbackFacade).rollBackUserAccount(captor.capture());
-    assertEquals(user, captor.getValue().getUser());
-    assertTrue(captor.getValue().isRollBackUserAccount());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          ArgumentCaptor<RollbackUserAccountInformation> captor =
+              ArgumentCaptor.forClass(RollbackUserAccountInformation.class);
+          EasyRandom easyRandom = new EasyRandom();
+          UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
+          User user = easyRandom.nextObject(User.class);
+          RocketChatCredentials rocketChatCredentials =
+              easyRandom.nextObject(RocketChatCredentials.class);
+
+          when(userAgencyService.saveUserAgency(any()))
+              .thenThrow(new InternalServerErrorException(MESSAGE));
+
+          createUserChatRelationFacade.initializeUserChatAgencyRelation(
+              userDTO, user, rocketChatCredentials);
+
+          verify(rollbackFacade).rollBackUserAccount(captor.capture());
+          assertEquals(user, captor.getValue().getUser());
+          assertTrue(captor.getValue().isRollBackUserAccount());
+        });
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       initializeUserChatAgencyRelation_Should_ThrowBadRequestException_WhenAlreadyRegisteredToConsultingType() {
-    EasyRandom easyRandom = new EasyRandom();
-    UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
-    userDTO.setAgencyId(AGENCY_ID);
-    User user = easyRandom.nextObject(User.class);
-    RocketChatCredentials rocketChatCredentials =
-        easyRandom.nextObject(RocketChatCredentials.class);
-    UserAgency userAgency = new UserAgency(user, AGENCY_ID);
-    List<UserAgency> userAgencies = Collections.singletonList(userAgency);
-
-    when(userAgencyService.getUserAgenciesByUser(any())).thenReturn(userAgencies);
-
-    createUserChatRelationFacade.initializeUserChatAgencyRelation(
-        userDTO, user, rocketChatCredentials);
-
-    verify(userAgencyService, times(1)).saveUserAgency(any());
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          EasyRandom easyRandom = new EasyRandom();
+          UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
+          userDTO.setAgencyId(AGENCY_ID);
+          User user = easyRandom.nextObject(User.class);
+          RocketChatCredentials rocketChatCredentials =
+              easyRandom.nextObject(RocketChatCredentials.class);
+          UserAgency userAgency = new UserAgency(user, AGENCY_ID);
+          List<UserAgency> userAgencies = Collections.singletonList(userAgency);
+
+          when(userAgencyService.getUserAgenciesByUser(any())).thenReturn(userAgencies);
+
+          createUserChatRelationFacade.initializeUserChatAgencyRelation(
+              userDTO, user, rocketChatCredentials);
+
+          verify(userAgencyService, times(1)).saveUserAgency(any());
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/CreateUserFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/CreateUserFacadeTest.java
index 99e844996..d39a855aa 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/CreateUserFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/CreateUserFacadeTest.java
@@ -11,6 +11,7 @@
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyBoolean;
 import static org.mockito.ArgumentMatchers.anyString;
@@ -42,15 +43,15 @@
 import de.caritas.cob.userservice.consultingtypeservice.generated.web.model.ExtendedConsultingTypeResponseDTO;
 import de.caritas.cob.userservice.tenantservice.generated.web.model.RestrictedTenantDTO;
 import org.hamcrest.Matchers;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.http.HttpStatus;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class CreateUserFacadeTest {
 
   @InjectMocks private CreateUserFacade createUserFacade;
@@ -85,15 +86,19 @@ public class CreateUserFacadeTest {
     }
   }
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       createUserAccountWithInitializedConsultingType_Should_ThrowBadRequest_When_ProvidedConsultingTypeDoesNotMatchAgency() {
-    doNothing().when(userVerifier).checkIfUsernameIsAvailable(any());
-    doThrow(new BadRequestException(ERROR))
-        .when(agencyVerifier)
-        .checkIfConsultingTypeMatchesToAgency(any());
-
-    createUserFacade.createUserAccountWithInitializedConsultingType(USER_DTO_SUCHT);
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          doNothing().when(userVerifier).checkIfUsernameIsAvailable(any());
+          doThrow(new BadRequestException(ERROR))
+              .when(agencyVerifier)
+              .checkIfConsultingTypeMatchesToAgency(any());
+
+          createUserFacade.createUserAccountWithInitializedConsultingType(USER_DTO_SUCHT);
+        });
   }
 
   @Test
@@ -114,14 +119,17 @@ public class CreateUserFacadeTest {
     }
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       createUserAccountWithInitializedConsultingType_Should_ThrowInternalServerErrorException_When_CreateKeycloakUserReturnsNoUserId() {
-
-    when(keycloakService.createKeycloakUser(any()))
-        .thenReturn(KEYCLOAK_CREATE_USER_RESPONSE_DTO_WITHOUT_USER_ID);
-
-    createUserFacade.createUserAccountWithInitializedConsultingType(USER_DTO_SUCHT);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(keycloakService.createKeycloakUser(any()))
+              .thenReturn(KEYCLOAK_CREATE_USER_RESPONSE_DTO_WITHOUT_USER_ID);
+
+          createUserFacade.createUserAccountWithInitializedConsultingType(USER_DTO_SUCHT);
+        });
   }
 
   @Test
@@ -185,39 +193,53 @@ public class CreateUserFacadeTest {
     verify(rollbackFacade, times(0)).rollBackUserAccount(any());
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       updateKeycloakAccountAndCreateDatabaseUserAccount_Should_ThrowInternalServerErrorExceptionAndRollbackUserAccount_When_UpdateKeycloakPwFails() {
-    doThrow(new RuntimeException()).when(keycloakService).updatePassword(anyString(), anyString());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new RuntimeException())
+              .when(keycloakService)
+              .updatePassword(anyString(), anyString());
 
-    createUserFacade.updateIdentityAndCreateAccount(USER_ID, USER_DTO_SUCHT, UserRole.USER);
+          createUserFacade.updateIdentityAndCreateAccount(USER_ID, USER_DTO_SUCHT, UserRole.USER);
 
-    verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+          verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       updateKeycloakAccountAndCreateDatabaseUserAccount_Should_ThrowInternalServerErrorExceptionAndRollbackUserAccount_When_UpdateKeycloakRoleFails() {
-    doThrow(new RuntimeException())
-        .when(keycloakService)
-        .updateRole(anyString(), any(UserRole.class));
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new RuntimeException())
+              .when(keycloakService)
+              .updateRole(anyString(), any(UserRole.class));
 
-    createUserFacade.updateIdentityAndCreateAccount(USER_ID, USER_DTO_SUCHT, UserRole.USER);
+          createUserFacade.updateIdentityAndCreateAccount(USER_ID, USER_DTO_SUCHT, UserRole.USER);
 
-    verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+          verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       updateKeycloakAccountAndCreateDatabaseUserAccount_Should_ThrowInternalServerErrorExceptionAndRollbackUserAccount_When_CreateDbUserFails() {
-    when(consultingTypeManager.getConsultingTypeSettings(any()))
-        .thenReturn(CONSULTING_TYPE_SETTINGS_KREUZBUND);
-    doNothing().when(keycloakService).updatePassword(anyString(), anyString());
-    when(userService.createUser(any(), any(), any(), any(), anyBoolean(), any()))
-        .thenThrow(new IllegalArgumentException());
-
-    createUserFacade.updateIdentityAndCreateAccount(USER_ID, USER_DTO_SUCHT, UserRole.USER);
-
-    verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultingTypeManager.getConsultingTypeSettings(any()))
+              .thenReturn(CONSULTING_TYPE_SETTINGS_KREUZBUND);
+          doNothing().when(keycloakService).updatePassword(anyString(), anyString());
+          when(userService.createUser(any(), any(), any(), any(), anyBoolean(), any()))
+              .thenThrow(new IllegalArgumentException());
+
+          createUserFacade.updateIdentityAndCreateAccount(USER_ID, USER_DTO_SUCHT, UserRole.USER);
+
+          verify(rollbackFacade, times(1)).rollBackUserAccount(any());
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/EmailNotificationFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/EmailNotificationFacadeTest.java
index b46af6563..2ff63c943 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/EmailNotificationFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/EmailNotificationFacadeTest.java
@@ -23,6 +23,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERNAME_ENCODED;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_ID;
 import static org.assertj.core.api.AssertionsForInterfaceTypes.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.atLeastOnce;
@@ -84,19 +85,22 @@
 import java.util.Optional;
 import java.util.Set;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.mockito.Spy;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 import org.slf4j.Logger;
 import org.springframework.test.util.ReflectionTestUtils;
 
-@RunWith(MockitoJUnitRunner.class)
-public class EmailNotificationFacadeTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class EmailNotificationFacadeTest {
 
   private final Consultant CONSULTANT =
       new Consultant(
@@ -472,8 +476,8 @@ public class EmailNotificationFacadeTest {
 
   @Mock TenantTemplateSupplier tenantTemplateSupplier;
 
-  @Before
-  public void setup() throws NoSuchFieldException, SecurityException {
+  @BeforeEach
+  void setup() throws NoSuchFieldException, SecurityException {
     when(identityClientConfig.getEmailDummySuffix()).thenReturn(FIELD_VALUE_EMAIL_DUMMY_SUFFIX);
     ReflectionTestUtils.setField(
         emailNotificationFacade,
@@ -492,7 +496,7 @@ public void setup() throws NoSuchFieldException, SecurityException {
   }
 
   @Test
-  public void
+  void
       sendNewEnquiryEmailNotification_Should_SendEmailNotificationViaMailServiceHelperToConsultants() {
     givenNewEnquiryMailSupplierReturnNonEmptyMails();
     var session = givenEnquirySession();
@@ -503,7 +507,7 @@ public void setup() throws NoSuchFieldException, SecurityException {
   }
 
   @Test
-  public void
+  void
       sendNewEnquiryEmailNotification_ShouldNot_SendEmailNotificationViaMailServiceHelperToUser() {
     givenNewEnquiryMailSupplierReturnNonEmptyMails();
     var session = givenEnquirySession();
@@ -514,7 +518,7 @@ public void setup() throws NoSuchFieldException, SecurityException {
   }
 
   @Test
-  public void sendNewEnquiryEmailNotification_Should_SetCurrentTenantContextFromSession() {
+  void sendNewEnquiryEmailNotification_Should_SetCurrentTenantContextFromSession() {
     assertThat(TenantContext.getCurrentTenant()).isNull();
     givenNewEnquiryMailSupplierReturnNonEmptyMails();
     var session = givenEnquirySession();
@@ -543,14 +547,14 @@ private List<MailDTO> getMailDTOS() {
   }
 
   @Test
-  public void sendNewEnquiryEmailNotification_ShouldNot_SendEmailWhenGeneratedEmailListIsEmpty() {
+  void sendNewEnquiryEmailNotification_ShouldNot_SendEmailWhenGeneratedEmailListIsEmpty() {
     emailNotificationFacade.sendNewEnquiryEmailNotification(SESSION, null);
 
     verify(mailService, times(0)).sendEmailNotification(Mockito.any(MailsDTO.class));
   }
 
   @Test
-  public void sendNewEnquiryEmailNotification_Should_LogError_WhenSendEmailFails() {
+  void sendNewEnquiryEmailNotification_Should_LogError_WhenSendEmailFails() {
     var session = givenEnquirySession();
     EmailNotificationException emailNotificationException =
         new EmailNotificationException(new Exception());
@@ -563,7 +567,7 @@ public void sendNewEnquiryEmailNotification_Should_LogError_WhenSendEmailFails()
 
   /** Method: sendNewMessageNotification */
   @Test
-  public void
+  void
       sendNewMessageNotification_Should_SendEmailNotificationViaMailServiceHelperToConsultant_WhenCalledAsUserAuthorityAndIsTeamSession() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -579,7 +583,7 @@ public void sendNewEnquiryEmailNotification_Should_LogError_WhenSendEmailFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_ShouldNot_SendEmailNotificationToUser_WhenCalledAsUserAuthorityAndIsTeamSession() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -595,7 +599,7 @@ public void sendNewEnquiryEmailNotification_Should_LogError_WhenSendEmailFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_ShouldNot_SendEmail_WhenMailListIsEmptyAndCalledAsUserAuthorityAndIsTeamSession() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -610,7 +614,7 @@ public void sendNewEnquiryEmailNotification_Should_LogError_WhenSendEmailFails()
   }
 
   @Test
-  public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails() {
+  void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails() {
     InternalServerErrorException serviceException = new InternalServerErrorException(ERROR_MSG);
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
         .thenThrow(serviceException);
@@ -620,7 +624,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_ShouldNot_SendEmailAndLogEmailNotificationFacadeError_WhenSessionIsNullOrEmpty() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -633,7 +637,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_ShouldNot_SendEmailAndLogEmailNotificationFacadeError_WhenSessionIsNotInProgress() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -646,7 +650,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_ShouldNot_SendEmail_WhenCalledAsUserAuthorityAndIsSingleSessionAndConsultantHasNoEmailProvided() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -658,7 +662,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_Should_SendEmailNotificationViaMailServiceHelper_WhenCalledAsUserAuthorityAndIsSingleSession() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -670,7 +674,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_ShouldNot_SendEmailAndLogEmailNotificationFacadeWarning_When_GetSessionFails() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, CONSULTANT_ID, CONSULTANT_ROLES))
@@ -684,7 +688,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_Should_LogEmailNotificationFacadeError_When_ErrorOccursDuringMailTransmission() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, CONSULTANT_ID, CONSULTANT_ROLES))
@@ -699,7 +703,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_ShouldNot_SendEmail_WhenCalledAsConsultantAuthorityAndAskerHasNoEmailProvided() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, CONSULTANT_ID, CONSULTANT_ROLES))
@@ -712,7 +716,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_Should_SendEmailToUserWithEncodedUsernames_WhenCalledAsConsultantAuthorityAndAskerHasEmail() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, CONSULTANT_ID, CONSULTANT_ROLES))
@@ -725,7 +729,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_Should_SendEmailToAllConsultants_WhenIsTeamSessionAndConsultingTypeSettingsToSendToAllTeamConsultantsIsTrue() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -740,7 +744,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewMessageNotification_Should_SendEmailToAssignConsultantOnly_WhenIsTeamSessionAndConsultingTypeSettingsToSendToAllTeamConsultantsIsFalse() {
 
     when(sessionService.getSessionByGroupIdAndUser(RC_GROUP_ID, USER_ID, USER_ROLES))
@@ -755,7 +759,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
 
   /** Method: sendNewFeedbackMessageNotification */
   @Test
-  public void
+  void
       sendNewFeedbackMessageNotification_Should_SendEmailToAllFeedbackChatGroupMembersWithDecodedUsernames_WhenAssignedConsultantWroteAFeedbackMessage() {
     when(consultantService.getConsultant(CONSULTANT_ID)).thenReturn(Optional.of(CONSULTANT));
     when(sessionService.getSessionByFeedbackGroupId(RC_FEEDBACK_GROUP_ID)).thenReturn(SESSION);
@@ -772,7 +776,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewFeedbackMessageNotification_Should_SendEmailToAssignedConsultantWithDecodedUsername_WhenOtherConsultantWrote() {
 
     when(consultantService.getConsultant(CONSULTANT_ID_2)).thenReturn(Optional.of(CONSULTANT2));
@@ -785,7 +789,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewFeedbackMessageNotification_Should_LogErrorAndSendNoMails_WhenCallingConsultantIsNotFound() {
 
     emailNotificationFacade.sendNewFeedbackMessageNotification(
@@ -795,7 +799,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewFeedbackMessageNotification_Should_LogErrorAndSendNoMails_WhenSessionIsNotFound() {
 
     when(sessionService.getSessionByFeedbackGroupId(RC_FEEDBACK_GROUP_ID)).thenReturn(null);
@@ -807,7 +811,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void
+  void
       sendNewFeedbackMessageNotification_Should_LogErrorAndSendNoMails_WhenNoConsultantIsAssignedToSession() {
 
     when(sessionService.getSessionByFeedbackGroupId(RC_FEEDBACK_GROUP_ID))
@@ -820,7 +824,7 @@ public void sendNewMessageNotification_Should_LogError_WhenSessionServiceFails()
   }
 
   @Test
-  public void sendAssignEnquiryEmailNotification_Should_SendEmail_WhenAllParametersAreValid() {
+  void sendAssignEnquiryEmailNotification_Should_SendEmail_WhenAllParametersAreValid() {
 
     when(consultantService.getConsultant(CONSULTANT_ID_2)).thenReturn(Optional.of(CONSULTANT2));
     emailNotificationFacade.sendAssignEnquiryEmailNotification(
@@ -830,7 +834,7 @@ public void sendAssignEnquiryEmailNotification_Should_SendEmail_WhenAllParameter
   }
 
   @Test
-  public void
+  void
       sendAssignEnquiryEmailNotification_Should_LogErrorAndSendNoMails_WhenReceiverConsultantIsNull() {
     emailNotificationFacade.sendAssignEnquiryEmailNotification(
         null, CONSULTANT_ID_2, USERNAME, null);
@@ -838,7 +842,7 @@ public void sendAssignEnquiryEmailNotification_Should_SendEmail_WhenAllParameter
   }
 
   @Test
-  public void
+  void
       sendAssignEnquiryEmailNotification_Should_LogErrorAndSendNoMails_WhenReceiverConsultantIsMissingEmailAddress() {
     emailNotificationFacade.sendAssignEnquiryEmailNotification(
         CONSULTANT_WITHOUT_MAIL, CONSULTANT_ID_2, USERNAME, null);
@@ -847,7 +851,7 @@ public void sendAssignEnquiryEmailNotification_Should_SendEmail_WhenAllParameter
   }
 
   @Test
-  public void
+  void
       sendAssignEnquiryEmailNotification_Should_LogErrorAndSendNoMails_WhenSenderConsultantIsNotFound() {
 
     when(consultantService.getConsultant(Mockito.anyString())).thenReturn(Optional.empty());
@@ -858,7 +862,7 @@ public void sendAssignEnquiryEmailNotification_Should_SendEmail_WhenAllParameter
   }
 
   @Test
-  public void sendNewMessageNotification_ShouldNot_LogError_When_SessionStatusIsNew() {
+  void sendNewMessageNotification_ShouldNot_LogError_When_SessionStatusIsNew() {
     Session session = mock(Session.class);
     when(session.getStatus()).thenReturn(SessionStatus.NEW);
     when(session.getUser()).thenReturn(USER);
@@ -871,7 +875,7 @@ public void sendNewMessageNotification_ShouldNot_LogError_When_SessionStatusIsNe
   }
 
   @Test
-  public void
+  void
       sendAssignEnquiryEmailNotification_Should_LogError_When_MailServiceHelperThrowsException() {
     doThrow(new RuntimeException("unexpected")).when(mailService).sendEmailNotification(any());
     when(consultantService.getConsultant(any())).thenReturn(Optional.of(CONSULTANT));
@@ -880,7 +884,7 @@ public void sendNewMessageNotification_ShouldNot_LogError_When_SessionStatusIsNe
   }
 
   @Test
-  public void
+  void
       sendAssignEnquiryEmailNotification_Should_LogError_When_SessionServiceThrowsRuntimeException() {
     when(sessionService.getSessionByFeedbackGroupId(any())).thenThrow(new RuntimeException(""));
 
@@ -890,7 +894,7 @@ public void sendNewMessageNotification_ShouldNot_LogError_When_SessionStatusIsNe
   }
 
   @Test
-  public void
+  void
       sendNewEnquiryEmailNotification_Should_notSendAnyMail_When_sessionHasAlreadyAConsultantAssigned() {
     emailNotificationFacade.sendNewEnquiryEmailNotification(
         new EasyRandom().nextObject(Session.class), null);
@@ -899,7 +903,7 @@ public void sendNewMessageNotification_ShouldNot_LogError_When_SessionStatusIsNe
   }
 
   @Test
-  public void sendReassignRequestNotification_Should_SendEmail_When_askerHasValidMailAddress() {
+  void sendReassignRequestNotification_Should_SendEmail_When_askerHasValidMailAddress() {
     var session = new EasyRandom().nextObject(Session.class);
     when(sessionService.getSessionByGroupId(any())).thenReturn(session);
     session.getUser().setEmail("mail@valid.de");
@@ -914,7 +918,7 @@ public void sendReassignRequestNotification_Should_SendEmail_When_askerHasValidM
   }
 
   @Test
-  public void sendReassignRequestNotification_ShouldNot_SendEmail_When_askerHasDummyMailAddress() {
+  void sendReassignRequestNotification_ShouldNot_SendEmail_When_askerHasDummyMailAddress() {
     var session = new EasyRandom().nextObject(Session.class);
     when(sessionService.getSessionByGroupId(any())).thenReturn(session);
     session.getUser().setEmail("mail@" + FIELD_VALUE_EMAIL_DUMMY_SUFFIX);
@@ -925,7 +929,7 @@ public void sendReassignRequestNotification_ShouldNot_SendEmail_When_askerHasDum
   }
 
   @Test
-  public void
+  void
       sendReassignRequestNotification_Should_SendEmail_When_NewNotificationModeEnabledAndAskerDoesNotWantToReceiveNotifications() {
     var session = new EasyRandom().nextObject(Session.class);
     when(sessionService.getSessionByGroupId(any())).thenReturn(session);
@@ -944,7 +948,7 @@ public void sendReassignRequestNotification_ShouldNot_SendEmail_When_askerHasDum
   }
 
   @Test
-  public void sendReassignConfirmationNotification_Should_sendEmail_When_consultantsExists() {
+  void sendReassignConfirmationNotification_Should_sendEmail_When_consultantsExists() {
     var randomConsultant = new EasyRandom().nextObject(Consultant.class);
     when(consultantService.getConsultant(any())).thenReturn(Optional.of(randomConsultant));
     var reassignmentNotification = new EasyRandom().nextObject(ReassignmentNotificationDTO.class);
@@ -957,7 +961,7 @@ public void sendReassignConfirmationNotification_Should_sendEmail_When_consultan
   }
 
   @Test
-  public void
+  void
       sendReassignConfirmationNotification_Should_sendNotEmail_When_newEmailNotificationsEnabledAndConsultantsDoesNotWantToReceiveNotifications() {
     var randomConsultant = new EasyRandom().nextObject(Consultant.class);
     when(consultantService.getConsultant(any())).thenReturn(Optional.of(randomConsultant));
@@ -976,7 +980,7 @@ public void sendReassignConfirmationNotification_Should_sendEmail_When_consultan
   }
 
   @Test
-  public void
+  void
       sendReassignConfirmationNotification_Should_sendEmail_When_newEmailNotificationsEnabledAndConsultantsDoesWantsToReceiveNotifications() {
     var randomConsultant = new EasyRandom().nextObject(Consultant.class);
     when(consultantService.getConsultant(any())).thenReturn(Optional.of(randomConsultant));
@@ -994,12 +998,18 @@ public void sendReassignConfirmationNotification_Should_sendEmail_When_consultan
     verifyAsync(a -> mailService.sendEmailNotification(Mockito.any()));
   }
 
-  @Test(expected = NotFoundException.class)
-  public void
+  @Test
+  void
       sendReassignConfirmationNotification_ShouldThrow_NotFoundEception_When_consultantDoesNotExist() {
-    var reassignmentNotification = new EasyRandom().nextObject(ReassignmentNotificationDTO.class);
-    when(consultantService.getConsultant(any())).thenReturn(Optional.empty());
-
-    emailNotificationFacade.sendReassignConfirmationNotification(reassignmentNotification, null);
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          var reassignmentNotification =
+              new EasyRandom().nextObject(ReassignmentNotificationDTO.class);
+          when(consultantService.getConsultant(any())).thenReturn(Optional.empty());
+
+          emailNotificationFacade.sendReassignConfirmationNotification(
+              reassignmentNotification, null);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/GetChatFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/GetChatFacadeTest.java
index c31dd342a..d909f1229 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/GetChatFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/GetChatFacadeTest.java
@@ -5,9 +5,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTANT;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -19,13 +17,13 @@
 import de.caritas.cob.userservice.api.helper.ChatPermissionVerifier;
 import de.caritas.cob.userservice.api.service.ChatService;
 import java.util.Optional;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class GetChatFacadeTest {
 
   @InjectMocks private GetChatFacade getChatFacade;
@@ -42,7 +40,7 @@ public void getChat_Should_ThrowNotFoundException_WhenChatDoesNotExist() {
       getChatFacade.getChat(CHAT_ID);
       fail("Expected exception: NotFoundException");
     } catch (NotFoundException notFoundException) {
-      assertTrue("Excepted NotFoundException thrown", true);
+      assertTrue(true, "Excepted NotFoundException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -59,7 +57,7 @@ public void getChat_Should_ThrowRequestForbiddenException_WhenConsultantHasNoPer
       getChatFacade.getChat(CHAT_ID);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException requestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -77,7 +75,7 @@ public void getChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermissio
       getChatFacade.getChat(CHAT_ID);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException requestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/GetChatMembersFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/GetChatMembersFacadeTest.java
index 267624977..249a92024 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/GetChatMembersFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/GetChatMembersFacadeTest.java
@@ -6,8 +6,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.GROUP_MEMBER_DTO_LIST;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.times;
@@ -29,13 +28,13 @@
 import de.caritas.cob.userservice.api.port.out.UserRepository;
 import de.caritas.cob.userservice.api.service.ChatService;
 import java.util.Optional;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class GetChatMembersFacadeTest {
 
   @InjectMocks private GetChatMembersFacade getChatMembersFacade;
@@ -61,7 +60,7 @@ public void getChatMembers_Should_ThrowNotFoundException_WhenChatDoesNotExist()
       getChatMembersFacade.getChatMembers(CHAT_ID);
       fail("Expected exception: NotFoundException");
     } catch (NotFoundException notFoundException) {
-      assertTrue("Excepted NotFoundException thrown", true);
+      assertTrue(true, "Excepted NotFoundException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -77,7 +76,7 @@ public void getChatMembers_Should_ThrowConflictException_WhenChatIsNotActive() {
       getChatMembersFacade.getChatMembers(CHAT_ID);
       fail("Expected exception: ConflictException");
     } catch (ConflictException conflictException) {
-      assertTrue("Excepted ConflictException thrown", true);
+      assertTrue(true, "Excepted ConflictException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -95,7 +94,7 @@ public void getChatMembers_Should_ThrowConflictException_WhenChatIsNotActive() {
       getChatMembersFacade.getChatMembers(CHAT_ID);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException requestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -114,7 +113,7 @@ public void getChatMembers_Should_ThrowConflictException_WhenChatIsNotActive() {
       getChatMembersFacade.getChatMembers(CHAT_ID);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException requestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -153,25 +152,34 @@ public void getChatMembers_Should_ReturnValidChatMembersResponseDTOForConsultant
     verify(chatPermissionVerifier, times(1)).verifyPermissionForChat(ACTIVE_CHAT);
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void getChatMembers_Should_throwInternalServerErrorException_When_rocketChatAccessFails()
       throws Exception {
-    when(chatService.getChat(ACTIVE_CHAT.getId())).thenReturn(Optional.of(ACTIVE_CHAT));
-    when(rocketChatService.getStandardMembersOfGroup(ACTIVE_CHAT.getGroupId()))
-        .thenThrow(new RocketChatGetGroupMembersException(""));
-
-    getChatMembersFacade.getChatMembers(ACTIVE_CHAT.getId());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(chatService.getChat(ACTIVE_CHAT.getId())).thenReturn(Optional.of(ACTIVE_CHAT));
+          when(rocketChatService.getStandardMembersOfGroup(ACTIVE_CHAT.getGroupId()))
+              .thenThrow(new RocketChatGetGroupMembersException(""));
+
+          getChatMembersFacade.getChatMembers(ACTIVE_CHAT.getId());
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void getChatMembers_Should_throwInternalServerErrorException_When_rocketChatGroupHasNoId()
       throws Exception {
-    Chat activeChatWithoutId = new Chat();
-    activeChatWithoutId.setActive(true);
-    when(chatService.getChat(ACTIVE_CHAT.getId())).thenReturn(Optional.of(activeChatWithoutId));
-    when(rocketChatService.getStandardMembersOfGroup(ACTIVE_CHAT.getGroupId()))
-        .thenThrow(new RocketChatGetGroupMembersException(""));
-
-    getChatMembersFacade.getChatMembers(ACTIVE_CHAT.getId());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          Chat activeChatWithoutId = new Chat();
+          activeChatWithoutId.setActive(true);
+          when(chatService.getChat(ACTIVE_CHAT.getId()))
+              .thenReturn(Optional.of(activeChatWithoutId));
+          when(rocketChatService.getStandardMembersOfGroup(ACTIVE_CHAT.getGroupId()))
+              .thenThrow(new RocketChatGetGroupMembersException(""));
+
+          getChatMembersFacade.getChatMembers(ACTIVE_CHAT.getId());
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/JoinAndLeaveChatFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/JoinAndLeaveChatFacadeTest.java
index 99e82c437..b8119c7a4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/JoinAndLeaveChatFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/JoinAndLeaveChatFacadeTest.java
@@ -4,8 +4,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CHAT_ID;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTANT;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.RC_USER_ID;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
@@ -37,14 +36,14 @@
 import java.util.List;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
-public class JoinAndLeaveChatFacadeTest {
+@ExtendWith(MockitoExtension.class)
+class JoinAndLeaveChatFacadeTest {
 
   private static final EasyRandom easyRandom = new EasyRandom();
 
@@ -67,21 +66,21 @@ public class JoinAndLeaveChatFacadeTest {
   @Mock private RocketChatService rocketChatService;
 
   @Test
-  public void joinChat_Should_ThrowNotFoundException_WhenChatDoesNotExist() {
+  void joinChat_Should_ThrowNotFoundException_WhenChatDoesNotExist() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.empty());
 
     try {
       joinAndLeaveChatFacade.joinChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: NotFoundException");
     } catch (NotFoundException notFoundException) {
-      assertTrue("Excepted NotFoundException thrown", true);
+      assertTrue(true, "Excepted NotFoundException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
   }
 
   @Test
-  public void joinChat_Should_ThrowConflictException_WhenChatIsNotActive() {
+  void joinChat_Should_ThrowConflictException_WhenChatIsNotActive() {
     Chat inactiveChat = mock(Chat.class);
     when(inactiveChat.isActive()).thenReturn(false);
 
@@ -91,14 +90,14 @@ public void joinChat_Should_ThrowConflictException_WhenChatIsNotActive() {
       joinAndLeaveChatFacade.joinChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: ConflictException");
     } catch (ConflictException conflictException) {
-      assertTrue("Excepted ConflictException thrown", true);
+      assertTrue(true, "Excepted ConflictException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
   }
 
   @Test
-  public void
+  void
       joinChat_Should_ThrowRequestForbiddenException_WhenConsultantHasNoPermissionForChat() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     doThrow(new ForbiddenException(""))
@@ -109,7 +108,7 @@ public void joinChat_Should_ThrowConflictException_WhenChatIsNotActive() {
       joinAndLeaveChatFacade.joinChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException requestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -117,7 +116,7 @@ public void joinChat_Should_ThrowConflictException_WhenChatIsNotActive() {
   }
 
   @Test
-  public void joinChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermissionForChat() {
+  void joinChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermissionForChat() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     doThrow(new ForbiddenException(""))
         .when(chatPermissionVerifier)
@@ -127,7 +126,7 @@ public void joinChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermissi
       joinAndLeaveChatFacade.joinChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException requestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -135,7 +134,7 @@ public void joinChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermissi
   }
 
   @Test
-  public void joinChat_Should_ThrowInternalServerErrorException_WhenConsultantHasNoRocketChatId() {
+  void joinChat_Should_ThrowInternalServerErrorException_WhenConsultantHasNoRocketChatId() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
         .thenReturn(Optional.of(consultant));
@@ -145,7 +144,7 @@ public void joinChat_Should_ThrowInternalServerErrorException_WhenConsultantHasN
       joinAndLeaveChatFacade.joinChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException internalServerErrorException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -155,7 +154,7 @@ public void joinChat_Should_ThrowInternalServerErrorException_WhenConsultantHasN
   }
 
   @Test
-  public void joinChat_Should_ThrowInternalServerErrorException_WhenUserHasNoRocketChatId() {
+  void joinChat_Should_ThrowInternalServerErrorException_WhenUserHasNoRocketChatId() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     when(userService.getUserViaAuthenticatedUser(authenticatedUser)).thenReturn(Optional.of(user));
     when(user.getRcUserId()).thenReturn(null);
@@ -164,7 +163,7 @@ public void joinChat_Should_ThrowInternalServerErrorException_WhenUserHasNoRocke
       joinAndLeaveChatFacade.joinChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException internalServerErrorException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -173,7 +172,7 @@ public void joinChat_Should_ThrowInternalServerErrorException_WhenUserHasNoRocke
   }
 
   @Test
-  public void joinChat_Should_AddConsultantToRocketChatGroup()
+  void joinChat_Should_AddConsultantToRocketChatGroup()
       throws RocketChatAddUserToGroupException {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
@@ -186,7 +185,7 @@ public void joinChat_Should_AddConsultantToRocketChatGroup()
   }
 
   @Test
-  public void joinChat_Should_AddUserToRocketChatGroup() throws RocketChatAddUserToGroupException {
+  void joinChat_Should_AddUserToRocketChatGroup() throws RocketChatAddUserToGroupException {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     when(userService.getUserViaAuthenticatedUser(authenticatedUser)).thenReturn(Optional.of(user));
     when(user.getRcUserId()).thenReturn(RC_USER_ID);
@@ -197,21 +196,21 @@ public void joinChat_Should_AddUserToRocketChatGroup() throws RocketChatAddUserT
   }
 
   @Test
-  public void leaveChat_Should_ThrowNotFoundException_WhenChatDoesNotExist() {
+  void leaveChat_Should_ThrowNotFoundException_WhenChatDoesNotExist() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.empty());
 
     try {
       joinAndLeaveChatFacade.leaveChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: NotFoundException");
     } catch (NotFoundException notFoundException) {
-      assertTrue("Excepted NotFoundException thrown", true);
+      assertTrue(true, "Excepted NotFoundException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
   }
 
   @Test
-  public void leaveChat_Should_ThrowConflictException_WhenChatIsNotActive() {
+  void leaveChat_Should_ThrowConflictException_WhenChatIsNotActive() {
     Chat inactiveChat = mock(Chat.class);
     when(inactiveChat.isActive()).thenReturn(false);
 
@@ -221,14 +220,14 @@ public void leaveChat_Should_ThrowConflictException_WhenChatIsNotActive() {
       joinAndLeaveChatFacade.leaveChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: ConflictException");
     } catch (ConflictException conflictException) {
-      assertTrue("Excepted ConflictException thrown", true);
+      assertTrue(true, "Excepted ConflictException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
   }
 
   @Test
-  public void
+  void
       leaveChat_Should_ThrowRequestForbiddenException_WhenConsultantHasNoPermissionForChat() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     doThrow(new ForbiddenException(""))
@@ -239,7 +238,7 @@ public void leaveChat_Should_ThrowConflictException_WhenChatIsNotActive() {
       joinAndLeaveChatFacade.leaveChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException requestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -247,7 +246,7 @@ public void leaveChat_Should_ThrowConflictException_WhenChatIsNotActive() {
   }
 
   @Test
-  public void leaveChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermissionForChat() {
+  void leaveChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermissionForChat() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     doThrow(new ForbiddenException(""))
         .when(chatPermissionVerifier)
@@ -257,7 +256,7 @@ public void leaveChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermiss
       joinAndLeaveChatFacade.leaveChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException requestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -265,7 +264,7 @@ public void leaveChat_Should_ThrowRequestForbiddenException_WhenUserHasNoPermiss
   }
 
   @Test
-  public void leaveChat_Should_ThrowInternalServerErrorException_WhenConsultantHasNoRocketChatId() {
+  void leaveChat_Should_ThrowInternalServerErrorException_WhenConsultantHasNoRocketChatId() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
         .thenReturn(Optional.of(consultant));
@@ -275,7 +274,7 @@ public void leaveChat_Should_ThrowInternalServerErrorException_WhenConsultantHas
       joinAndLeaveChatFacade.leaveChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException internalServerErrorException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -285,7 +284,7 @@ public void leaveChat_Should_ThrowInternalServerErrorException_WhenConsultantHas
   }
 
   @Test
-  public void leaveChat_Should_ThrowInternalServerErrorException_WhenUserHasNoRocketChatId() {
+  void leaveChat_Should_ThrowInternalServerErrorException_WhenUserHasNoRocketChatId() {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     when(userService.getUserViaAuthenticatedUser(authenticatedUser)).thenReturn(Optional.of(user));
     when(user.getRcUserId()).thenReturn(null);
@@ -294,7 +293,7 @@ public void leaveChat_Should_ThrowInternalServerErrorException_WhenUserHasNoRock
       joinAndLeaveChatFacade.leaveChat(CHAT_ID, authenticatedUser);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException internalServerErrorException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
 
     verify(chatService, times(1)).getChat(CHAT_ID);
@@ -303,7 +302,7 @@ public void leaveChat_Should_ThrowInternalServerErrorException_WhenUserHasNoRock
   }
 
   @Test
-  public void leaveChat_Should_RemoveConsultantFromRocketChatGroup()
+  void leaveChat_Should_RemoveConsultantFromRocketChatGroup()
       throws RocketChatRemoveUserFromGroupException, RocketChatUserNotInitializedException,
           RocketChatGetGroupMembersException {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
@@ -318,22 +317,27 @@ public void leaveChat_Should_RemoveConsultantFromRocketChatGroup()
         .removeUserFromGroup(CONSULTANT.getRocketChatId(), ACTIVE_CHAT.getGroupId());
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       leaveChat_Should_throwInternalServerErrorException_When_rocketChatUserCanNotBeRemoved()
           throws RocketChatRemoveUserFromGroupException {
-    when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
-    when(userService.getUserViaAuthenticatedUser(authenticatedUser)).thenReturn(Optional.of(user));
-    when(user.getRcUserId()).thenReturn(RC_USER_ID);
-    doThrow(new RocketChatRemoveUserFromGroupException(""))
-        .when(rocketChatService)
-        .removeUserFromGroup(any(), any());
-
-    joinAndLeaveChatFacade.leaveChat(ACTIVE_CHAT.getId(), authenticatedUser);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
+          when(userService.getUserViaAuthenticatedUser(authenticatedUser))
+              .thenReturn(Optional.of(user));
+          when(user.getRcUserId()).thenReturn(RC_USER_ID);
+          doThrow(new RocketChatRemoveUserFromGroupException(""))
+              .when(rocketChatService)
+              .removeUserFromGroup(any(), any());
+
+          joinAndLeaveChatFacade.leaveChat(ACTIVE_CHAT.getId(), authenticatedUser);
+        });
   }
 
   @Test
-  public void leaveChatShouldNotDeleteChatsWhenStandardMemberInChat()
+  void leaveChatShouldNotDeleteChatsWhenStandardMemberInChat()
       throws RocketChatUserNotInitializedException, RocketChatGetGroupMembersException {
     when(chatService.getChat(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
     when(userService.getUserViaAuthenticatedUser(authenticatedUser)).thenReturn(Optional.of(user));
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/RocketChatFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/RocketChatFacadeTest.java
index 66ae65fdf..a00ab6503 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/RocketChatFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/RocketChatFacadeTest.java
@@ -2,6 +2,7 @@
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.hasSize;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
@@ -17,13 +18,13 @@
 import de.caritas.cob.userservice.api.exception.rocketchat.RocketChatLeaveFromGroupException;
 import de.caritas.cob.userservice.api.exception.rocketchat.RocketChatRemoveSystemMessagesException;
 import de.caritas.cob.userservice.api.exception.rocketchat.RocketChatRemoveUserFromGroupException;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocketChatFacadeTest {
 
   @InjectMocks private RocketChatFacade rocketChatFacade;
@@ -39,15 +40,19 @@ public void addUserToRocketChatGroup_Should_addUserToGroup() throws Exception {
     verify(this.rocketChatService, times(1)).leaveFromGroupAsTechnicalUser("group");
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       addUserToRocketChatGroup_Should_throwInternalServerErrorException_When_RocketChatAddUserToGroupExceptionIsThrown()
           throws RocketChatAddUserToGroupException {
-    doThrow(new RocketChatAddUserToGroupException(""))
-        .when(this.rocketChatService)
-        .addUserToGroup(anyString(), anyString());
-
-    this.rocketChatFacade.addUserToRocketChatGroup("user", "group");
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new RocketChatAddUserToGroupException(""))
+              .when(this.rocketChatService)
+              .addUserToGroup(anyString(), anyString());
+
+          this.rocketChatFacade.addUserToRocketChatGroup("user", "group");
+        });
   }
 
   @Test
@@ -61,15 +66,19 @@ public void addUserToRocketChatGroup_Should_addUserToGroup() throws Exception {
     verify(this.rocketChatService, times(1)).leaveFromGroupAsTechnicalUser("group");
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       removeSystemMessagesFromRocketChatGroup_Should_throwInternalServerErrorException_When_RocketChatRemoveSystemMessagesExceptionIsThrown()
           throws Exception {
-    doThrow(new RocketChatRemoveSystemMessagesException(""))
-        .when(this.rocketChatService)
-        .removeSystemMessages(anyString(), any(), any());
-
-    this.rocketChatFacade.removeSystemMessagesFromRocketChatGroup("group");
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new RocketChatRemoveSystemMessagesException(""))
+              .when(this.rocketChatService)
+              .removeSystemMessages(anyString(), any(), any());
+
+          this.rocketChatFacade.removeSystemMessagesFromRocketChatGroup("group");
+        });
   }
 
   @Test
@@ -81,12 +90,18 @@ public void retrieveRocketChatMembers_Should_retrieveRocketChatMembers() throws
     verify(this.rocketChatService, times(1)).leaveFromGroupAsTechnicalUser("group");
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       retrieveRocketChatMembers_Should_throwInternalServerErrorException_When_RocketChatGetGroupMembersException() {
-    doThrow(new MongoClientException("")).when(this.rocketChatService).getChatUsers(anyString());
-
-    this.rocketChatFacade.retrieveRocketChatMembers("group");
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new MongoClientException(""))
+              .when(this.rocketChatService)
+              .getChatUsers(anyString());
+
+          this.rocketChatFacade.retrieveRocketChatMembers("group");
+        });
   }
 
   @Test
@@ -96,15 +111,19 @@ public void addTechnicalUserToGroup_Should_addTechnicalUserToGroup() throws Exce
     verify(this.rocketChatService, times(1)).addTechnicalUserToGroup("group");
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       addTechnicalUserToGroup_Should_throwInternalServerErrorException_When_RocketChatGetGroupMembersException()
           throws Exception {
-    doThrow(new RocketChatAddUserToGroupException(""))
-        .when(this.rocketChatService)
-        .addTechnicalUserToGroup(anyString());
-
-    this.rocketChatFacade.addTechnicalUserToGroup("group");
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new RocketChatAddUserToGroupException(""))
+              .when(this.rocketChatService)
+              .addTechnicalUserToGroup(anyString());
+
+          this.rocketChatFacade.addTechnicalUserToGroup("group");
+        });
   }
 
   @Test
@@ -115,15 +134,19 @@ public void leaveFromGroupAsTechnicalUser_Should_leaveFromGroupAsTechnicalUser()
     verify(this.rocketChatService, times(1)).leaveFromGroupAsTechnicalUser("group");
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       leaveFromGroupAsTechnicalUser_Should_throwInternalServerErrorException_When_RocketChatLeaveFromGroupException()
           throws Exception {
-    doThrow(new RocketChatLeaveFromGroupException(""))
-        .when(this.rocketChatService)
-        .leaveFromGroupAsTechnicalUser(anyString());
-
-    this.rocketChatFacade.leaveFromGroupAsTechnicalUser("group");
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new RocketChatLeaveFromGroupException(""))
+              .when(this.rocketChatService)
+              .leaveFromGroupAsTechnicalUser(anyString());
+
+          this.rocketChatFacade.leaveFromGroupAsTechnicalUser("group");
+        });
   }
 
   @Test
@@ -133,15 +156,19 @@ public void removeUserFromGroup_Should_removeUserFromGroup() throws Exception {
     verify(this.rocketChatService, times(1)).removeUserFromGroup("user", "group");
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       removeUserFromGroup_Should_throwInternalServerErrorException_When_RocketChatRemoveUserFromGroupExceptionIsThrown()
           throws Exception {
-    doThrow(new RocketChatRemoveUserFromGroupException(""))
-        .when(this.rocketChatService)
-        .removeUserFromGroup(anyString(), anyString());
-
-    this.rocketChatFacade.removeUserFromGroup("user", "group");
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new RocketChatRemoveUserFromGroupException(""))
+              .when(this.rocketChatService)
+              .removeUserFromGroup(anyString(), anyString());
+
+          this.rocketChatFacade.removeUserFromGroup("user", "group");
+        });
   }
 
   @Test
@@ -151,14 +178,18 @@ public void getStandardMembersOfGroup_Should_getStandardMembersOfGroup() throws
     verify(this.rocketChatService, times(1)).getStandardMembersOfGroup("group");
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void getStandardMembersOfGroup_Should_throwInternalServerError_When_rocketChatAccessFails()
       throws Exception {
-    doThrow(new RocketChatGetGroupMembersException(""))
-        .when(this.rocketChatService)
-        .getStandardMembersOfGroup(any());
-
-    this.rocketChatFacade.getStandardMembersOfGroup("");
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          doThrow(new RocketChatGetGroupMembersException(""))
+              .when(this.rocketChatService)
+              .getStandardMembersOfGroup(any());
+
+          this.rocketChatFacade.getStandardMembersOfGroup("");
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/SessionArchiveServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/facade/SessionArchiveServiceIT.java
index d67afa7ea..96fb19459 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/SessionArchiveServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/SessionArchiveServiceIT.java
@@ -2,6 +2,7 @@
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -20,8 +21,7 @@
 import de.caritas.cob.userservice.api.testConfig.ConsultingTypeManagerTestConfig;
 import java.util.Optional;
 import java.util.UUID;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
@@ -29,9 +29,7 @@
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.context.annotation.Import;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
@@ -56,36 +54,50 @@ public void archiveSession_Should_ChangeStatusOfSession_WhenConsultantHasPermiss
     assertThat(session.get().getStatus(), is(SessionStatus.IN_ARCHIVE));
   }
 
-  @Test(expected = NotFoundException.class)
+  @Test
   public void archiveSession_Should_ThrowNotFoundException_WhenSessionIsNotFound() {
-    sessionArchiveService.archiveSession(99999999L);
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          sessionArchiveService.archiveSession(99999999L);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void archiveSession_Should_ThrowForbiddenException_WhenConsultantHasNoPermission() {
-
-    when(authenticatedUser.getUserId()).thenReturn("88613f5d-0d40-47e0-b323-e792e7fba3ed");
-    when(authenticatedUser.isConsultant()).thenReturn(true);
-    sessionArchiveService.archiveSession(1L);
-
-    verify(sessionRepository, times(0)).save(any());
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          when(authenticatedUser.getUserId()).thenReturn("88613f5d-0d40-47e0-b323-e792e7fba3ed");
+          when(authenticatedUser.isConsultant()).thenReturn(true);
+          sessionArchiveService.archiveSession(1L);
+
+          verify(sessionRepository, times(0)).save(any());
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void archiveSession_Should_ThrowForbiddenException_WhenUserHasNoPermission() {
-
-    when(authenticatedUser.getUserId()).thenReturn("88613f5d-0d40-47e0-b323-e792e7fba3ed");
-    when(authenticatedUser.isAdviceSeeker()).thenReturn(true);
-    sessionArchiveService.archiveSession(1L);
-
-    verify(sessionRepository, times(0)).save(any());
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          when(authenticatedUser.getUserId()).thenReturn("88613f5d-0d40-47e0-b323-e792e7fba3ed");
+          when(authenticatedUser.isAdviceSeeker()).thenReturn(true);
+          sessionArchiveService.archiveSession(1L);
+
+          verify(sessionRepository, times(0)).save(any());
+        });
   }
 
-  @Test(expected = ConflictException.class)
+  @Test
   public void archiveSession_Should_ThrowConflictException_WhenSessionIsNotInProgress() {
-    when(authenticatedUser.getUserId()).thenReturn("75abe824-fb42-476d-a52a-66660113bdcc");
+    assertThrows(
+        ConflictException.class,
+        () -> {
+          when(authenticatedUser.getUserId()).thenReturn("75abe824-fb42-476d-a52a-66660113bdcc");
 
-    sessionArchiveService.archiveSession(1214L);
+          sessionArchiveService.archiveSession(1214L);
+        });
   }
 
   @Test
@@ -114,21 +126,33 @@ public void reactivateSession_Should_ChangeStatusOfSession_WhenUserHasPermission
     assertThat(session.get().getStatus(), is(SessionStatus.IN_PROGRESS));
   }
 
-  @Test(expected = NotFoundException.class)
+  @Test
   public void reactivateSession_Should_ThrowNotFoundException_WhenSessionIsNotFound() {
-    sessionArchiveService.dearchiveSession(99999999L);
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          sessionArchiveService.dearchiveSession(99999999L);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void reactivateSession_Should_ThrowForbiddenException_WhenUserHasNoPermission() {
-    when(authenticatedUser.getUserId()).thenReturn(UUID.randomUUID().toString());
-    sessionArchiveService.dearchiveSession(1210L);
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          when(authenticatedUser.getUserId()).thenReturn(UUID.randomUUID().toString());
+          sessionArchiveService.dearchiveSession(1210L);
+        });
   }
 
-  @Test(expected = ConflictException.class)
+  @Test
   public void reactivateSession_Should_ThrowConflictException_WhenSessionIsNotInArchive() {
-    when(authenticatedUser.getUserId()).thenReturn("473f7c4b-f011-4fc2-847c-ceb636a5b399");
-    when(authenticatedUser.isConsultant()).thenReturn(true);
-    sessionArchiveService.dearchiveSession(1L);
+    assertThrows(
+        ConflictException.class,
+        () -> {
+          when(authenticatedUser.getUserId()).thenReturn("473f7c4b-f011-4fc2-847c-ceb636a5b399");
+          when(authenticatedUser.isConsultant()).thenReturn(true);
+          sessionArchiveService.dearchiveSession(1L);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/StartChatFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/StartChatFacadeTest.java
index 0f0f73fb4..ce2fc4a46 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/StartChatFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/StartChatFacadeTest.java
@@ -4,8 +4,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTANT;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.INACTIVE_CHAT;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.RC_GROUP_ID;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.times;
@@ -20,13 +19,13 @@
 import de.caritas.cob.userservice.api.helper.ChatPermissionVerifier;
 import de.caritas.cob.userservice.api.model.Chat;
 import de.caritas.cob.userservice.api.service.ChatService;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class StartChatFacadeTest {
 
   @InjectMocks private StartChatFacade startChatFacade;
@@ -48,7 +47,7 @@ public class StartChatFacadeTest {
       startChatFacade.startChat(ACTIVE_CHAT, CONSULTANT);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException sequestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
   }
 
@@ -60,7 +59,7 @@ public void startChat_Should_ThrowConflictException_WhenChatIsAlreadyStarted() {
       startChatFacade.startChat(ACTIVE_CHAT, CONSULTANT);
       fail("Expected exception: ConflictException");
     } catch (ConflictException conflictException) {
-      assertTrue("Excepted ConflictException thrown", true);
+      assertTrue(true, "Excepted ConflictException thrown");
     }
   }
 
@@ -75,7 +74,7 @@ public void startChat_Should_ThrowInternalServerError_WhenChatHasNoGroupId() {
       startChatFacade.startChat(chat, CONSULTANT);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException internalServerErrorException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
@@ -101,19 +100,23 @@ public void startChat_Should_SetChatActiveAndSaveChat() {
     verify(chatService, times(1)).saveChat(chat);
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       startChat_Should_throwInternalServerErrorException_When_userCanNotBeAddedToGroupInRocketChat()
           throws RocketChatAddUserToGroupException {
-    when(chat.getGroupId()).thenReturn(RC_GROUP_ID);
-    when(chatPermissionVerifier.hasSameAgencyAssigned(chat, CONSULTANT)).thenReturn(true);
-    doThrow(new RocketChatAddUserToGroupException(""))
-        .when(rocketChatService)
-        .addUserToGroup(any(), any());
-
-    startChatFacade.startChat(chat, CONSULTANT);
-
-    verify(chat, times(1)).setActive(true);
-    verify(chatService, times(1)).saveChat(chat);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(chat.getGroupId()).thenReturn(RC_GROUP_ID);
+          when(chatPermissionVerifier.hasSameAgencyAssigned(chat, CONSULTANT)).thenReturn(true);
+          doThrow(new RocketChatAddUserToGroupException(""))
+              .when(rocketChatService)
+              .addUserToGroup(any(), any());
+
+          startChatFacade.startChat(chat, CONSULTANT);
+
+          verify(chat, times(1)).setActive(true);
+          verify(chatService, times(1)).saveChat(chat);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/StopChatFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/StopChatFacadeTest.java
index 05f507e14..5216fdd79 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/StopChatFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/StopChatFacadeTest.java
@@ -2,8 +2,8 @@
 
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.ACTIVE_CHAT;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTANT;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -14,15 +14,18 @@
 import de.caritas.cob.userservice.api.exception.httpresponses.ForbiddenException;
 import de.caritas.cob.userservice.api.helper.ChatPermissionVerifier;
 import de.caritas.cob.userservice.api.model.Chat;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 
-@RunWith(MockitoJUnitRunner.class)
-public class StopChatFacadeTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class StopChatFacadeTest {
 
   @InjectMocks private StopChatFacade stopChatFacade;
 
@@ -32,27 +35,26 @@ public class StopChatFacadeTest {
 
   private final ActionCommandMockProvider mockProvider = new ActionCommandMockProvider();
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void setup() {
     when(this.actionsRegistry.buildContainerForType(Chat.class))
         .thenReturn(mockProvider.getActionContainer(Chat.class));
   }
 
   @Test
-  public void
-      stopChat_Should_ThrowRequestForbiddenException_When_ConsultantHasNoPermissionToStopChat() {
+  void stopChat_Should_ThrowRequestForbiddenException_When_ConsultantHasNoPermissionToStopChat() {
     when(chatPermissionVerifier.hasSameAgencyAssigned(ACTIVE_CHAT, CONSULTANT)).thenReturn(false);
 
     try {
       stopChatFacade.stopChat(ACTIVE_CHAT, CONSULTANT);
       fail("Expected exception: RequestForbiddenException");
     } catch (ForbiddenException sequestForbiddenException) {
-      assertTrue("Excepted RequestForbiddenException thrown", true);
+      assertTrue(true, "Excepted RequestForbiddenException thrown");
     }
   }
 
   @Test
-  public void stopChat_Should_executeExpectedAction_When_ConsultantHasPermissionToStopChat() {
+  void stopChat_Should_executeExpectedAction_When_ConsultantHasPermissionToStopChat() {
     when(chatPermissionVerifier.hasSameAgencyAssigned(ACTIVE_CHAT, CONSULTANT)).thenReturn(true);
 
     stopChatFacade.stopChat(ACTIVE_CHAT, CONSULTANT);
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/assignsession/AssignSessionFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/assignsession/AssignSessionFacadeTest.java
index 019c03fb1..afc02c6a0 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/assignsession/AssignSessionFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/assignsession/AssignSessionFacadeTest.java
@@ -54,14 +54,14 @@
 import javax.servlet.http.HttpServletRequest;
 import org.apache.commons.lang3.RandomStringUtils;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class AssignSessionFacadeTest {
 
   private static final EasyRandom easyRandom = new EasyRandom();
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/assignsession/UnauthorizedMembersProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/assignsession/UnauthorizedMembersProviderTest.java
index a3c41db31..df5d2add1 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/assignsession/UnauthorizedMembersProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/assignsession/UnauthorizedMembersProviderTest.java
@@ -13,7 +13,8 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.Mockito.when;
 import static org.springframework.test.util.ReflectionTestUtils.setField;
 
@@ -29,15 +30,18 @@
 import java.util.List;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 
-@RunWith(MockitoJUnitRunner.class)
-public class UnauthorizedMembersProviderTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class UnauthorizedMembersProviderTest {
 
   @InjectMocks UnauthorizedMembersProvider unauthorizedMembersProvider;
 
@@ -59,8 +63,8 @@ public class UnauthorizedMembersProviderTest {
   RocketChatCredentials techUserRcCredentials = easyRandom.nextObject(RocketChatCredentials.class);
   List<GroupMemberDTO> initialMemberList;
 
-  @Before
-  public void setup() throws NoSuchFieldException, SecurityException {
+  @BeforeEach
+  void setup() throws NoSuchFieldException, SecurityException {
     setField(
         unauthorizedMembersProvider,
         FIELD_NAME_ROCKET_CHAT_SYSTEM_USER_ID,
@@ -113,7 +117,7 @@ public void setup() throws NoSuchFieldException, SecurityException {
   }
 
   @Test
-  public void obtainConsultantsToRemoveShouldNotIncludeConsultantToAssignIfNotAssignedAlready()
+  void obtainConsultantsToRemoveShouldNotIncludeConsultantToAssignIfNotAssignedAlready()
       throws RocketChatUserNotInitializedException {
 
     var consultant = easyRandom.nextObject(Consultant.class);
@@ -131,7 +135,7 @@ public void obtainConsultantsToRemoveShouldNotIncludeConsultantToAssignIfNotAssi
   }
 
   @Test
-  public void obtainConsultantsToRemoveShouldNotIncludeConsultantToAssignIfAlreadyAssigned()
+  void obtainConsultantsToRemoveShouldNotIncludeConsultantToAssignIfAlreadyAssigned()
       throws RocketChatUserNotInitializedException {
 
     var consultant = easyRandom.nextObject(Consultant.class);
@@ -154,7 +158,7 @@ public void obtainConsultantsToRemoveShouldNotIncludeConsultantToAssignIfAlready
   }
 
   @Test
-  public void obtainConsultantsToRemoveShouldNotIncludeConsultantToKeep()
+  void obtainConsultantsToRemoveShouldNotIncludeConsultantToKeep()
       throws RocketChatUserNotInitializedException {
 
     var consultant = easyRandom.nextObject(Consultant.class);
@@ -186,7 +190,7 @@ public void obtainConsultantsToRemoveShouldNotIncludeConsultantToKeep()
   }
 
   @Test
-  public void
+  void
       obtainConsultantsToRemove_Should_ReturnCorrectUnauthorizedMemberList_When_SessionIsNoTeamSession()
           throws RocketChatUserNotInitializedException {
     newConsultant.setTeamConsultant(false);
@@ -210,7 +214,7 @@ public void obtainConsultantsToRemoveShouldNotIncludeConsultantToKeep()
   }
 
   @Test
-  public void
+  void
       obtainConsultantsToRemove_Should_ReturnCorrectUnauthorizedMemberList_When_SessionIsNormalTeamSession()
           throws RocketChatUserNotInitializedException {
     newConsultant.setTeamConsultant(true);
@@ -237,7 +241,7 @@ public void obtainConsultantsToRemoveShouldNotIncludeConsultantToKeep()
   }
 
   @Test
-  public void
+  void
       obtainConsultantsToRemove_Should_ReturnCorrectUnauthorizedMemberList_When_SessionIsFeedbackSessionForNormalGroup()
           throws RocketChatUserNotInitializedException {
     newConsultant.setTeamConsultant(true);
@@ -279,7 +283,7 @@ public void obtainConsultantsToRemoveShouldNotIncludeConsultantToKeep()
   }
 
   @Test
-  public void
+  void
       obtainConsultantsToRemove_Should_ReturnCorrectUnauthorizedMemberList_When_SessionIsFeedbackSessionForFeedbackGroup()
           throws RocketChatUserNotInitializedException {
     newConsultant.setTeamConsultant(true);
@@ -316,14 +320,20 @@ public void obtainConsultantsToRemoveShouldNotIncludeConsultantToKeep()
             normalConsultant, teamConsultant, teamConsultant2, peerConsultant, peerConsultant2));
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
-      obtainConsultantsToRemove_Should_ThrowInternalServerError_When_TechUserIsNotInitialized()
-          throws RocketChatUserNotInitializedException {
-    when(rocketChatCredentialsProvider.getTechnicalUser())
-        .thenThrow(new RocketChatUserNotInitializedException(""));
-
-    unauthorizedMembersProvider.obtainConsultantsToRemove(
-        RC_GROUP_ID, FEEDBACK_SESSION_WITH_ASKER_AND_CONSULTANT, newConsultant, initialMemberList);
+  @Test
+  void obtainConsultantsToRemove_Should_ThrowInternalServerError_When_TechUserIsNotInitialized()
+      throws RocketChatUserNotInitializedException {
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(rocketChatCredentialsProvider.getTechnicalUser())
+              .thenThrow(new RocketChatUserNotInitializedException(""));
+
+          unauthorizedMembersProvider.obtainConsultantsToRemove(
+              RC_GROUP_ID,
+              FEEDBACK_SESSION_WITH_ASKER_AND_CONSULTANT,
+              newConsultant,
+              initialMemberList);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/conversation/CreateAnonymousEnquiryFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/conversation/CreateAnonymousEnquiryFacadeTest.java
index 92e1d66f7..962e9e0f7 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/conversation/CreateAnonymousEnquiryFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/conversation/CreateAnonymousEnquiryFacadeTest.java
@@ -2,6 +2,7 @@
 
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTING_TYPE_ID_KREUZBUND;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTING_TYPE_ID_SUCHT;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -20,13 +21,13 @@
 import de.caritas.cob.userservice.api.model.Session;
 import de.caritas.cob.userservice.consultingtypeservice.generated.web.model.ExtendedConsultingTypeResponseDTO;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class CreateAnonymousEnquiryFacadeTest {
 
   @InjectMocks private CreateAnonymousEnquiryFacade createAnonymousEnquiryFacade;
@@ -38,23 +39,29 @@ public class CreateAnonymousEnquiryFacadeTest {
 
   EasyRandom easyRandom = new EasyRandom();
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void
       createAnonymousEnquiry_Should_ThrowBadRequestException_When_GivenConsultingTypeDoesNotSupportAnonymousConversations() {
-    CreateAnonymousEnquiryDTO anonymousEnquiryDTO =
-        easyRandom.nextObject(CreateAnonymousEnquiryDTO.class);
-    anonymousEnquiryDTO.setConsultingType(CONSULTING_TYPE_ID_KREUZBUND);
-    var consultingTypeResponseDTO = easyRandom.nextObject(ExtendedConsultingTypeResponseDTO.class);
-    consultingTypeResponseDTO.setIsAnonymousConversationAllowed(false);
-    when(consultingTypeManager.getConsultingTypeSettings(anonymousEnquiryDTO.getConsultingType()))
-        .thenReturn(consultingTypeResponseDTO);
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          CreateAnonymousEnquiryDTO anonymousEnquiryDTO =
+              easyRandom.nextObject(CreateAnonymousEnquiryDTO.class);
+          anonymousEnquiryDTO.setConsultingType(CONSULTING_TYPE_ID_KREUZBUND);
+          var consultingTypeResponseDTO =
+              easyRandom.nextObject(ExtendedConsultingTypeResponseDTO.class);
+          consultingTypeResponseDTO.setIsAnonymousConversationAllowed(false);
+          when(consultingTypeManager.getConsultingTypeSettings(
+                  anonymousEnquiryDTO.getConsultingType()))
+              .thenReturn(consultingTypeResponseDTO);
 
-    createAnonymousEnquiryFacade.createAnonymousEnquiry(anonymousEnquiryDTO);
+          createAnonymousEnquiryFacade.createAnonymousEnquiry(anonymousEnquiryDTO);
 
-    verifyNoInteractions(anonymousUserCreatorService);
-    verifyNoInteractions(anonymousConversationCreatorService);
-    verifyNoInteractions(usernameRegistry);
-    verifyNoInteractions(userHelper);
+          verifyNoInteractions(anonymousUserCreatorService);
+          verifyNoInteractions(anonymousConversationCreatorService);
+          verifyNoInteractions(usernameRegistry);
+          verifyNoInteractions(userHelper);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/rollback/RollbackFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/rollback/RollbackFacadeTest.java
index 63117d8c9..60472b079 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/rollback/RollbackFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/rollback/RollbackFacadeTest.java
@@ -14,13 +14,13 @@
 import de.caritas.cob.userservice.api.service.user.UserService;
 import de.caritas.cob.userservice.api.workflow.delete.service.DeleteUserAccountService;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RollbackFacadeTest {
 
   @InjectMocks private RollbackFacade rollbackFacade;
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/sessionlist/RocketChatRoomInformationProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/sessionlist/RocketChatRoomInformationProviderTest.java
index 5bc1ecfbb..4c1ab78d5 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/sessionlist/RocketChatRoomInformationProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/sessionlist/RocketChatRoomInformationProviderTest.java
@@ -13,10 +13,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.SUBSCRIPTIONS_UPDATE_LIST_DTO_WITH_ONE_FEEDBACK_UNREAD;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERS_ROOMS_LIST;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_DTO_3;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.adapters.rocketchat.RocketChatService;
@@ -26,13 +23,13 @@
 import java.util.Date;
 import java.util.Objects;
 import org.apache.commons.collections.CollectionUtils;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocketChatRoomInformationProviderTest {
 
   @InjectMocks private RocketChatRoomInformationProvider rocketChatRoomInformationProvider;
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/sessionlist/SessionListFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/sessionlist/SessionListFacadeTest.java
index 173b82d69..24165b61a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/sessionlist/SessionListFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/sessionlist/SessionListFacadeTest.java
@@ -14,9 +14,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_ID;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_SESSION_RESPONSE_SESSION_CHAT_DTO_LIST;
 import static java.util.Objects.nonNull;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.adapters.web.dto.ConsultantSessionListResponseDTO;
@@ -29,16 +27,16 @@
 import de.caritas.cob.userservice.api.service.session.SessionTopicEnrichmentService;
 import de.caritas.cob.userservice.api.service.sessionlist.ConsultantSessionListService;
 import de.caritas.cob.userservice.api.service.sessionlist.UserSessionListService;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.test.util.ReflectionTestUtils;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class SessionListFacadeTest {
 
   @InjectMocks private SessionListFacade sessionListFacade;
@@ -47,7 +45,7 @@ public class SessionListFacadeTest {
   @Mock private SessionTopicEnrichmentService sessionTopicEnrichmentService;
 
   /** Method: retrieveSessionsForAuthenticatedUser */
-  @Before
+  @BeforeEach
   public void setUp() {
     ReflectionTestUtils.setField(
         sessionListFacade, "sessionTopicEnrichmentService", sessionTopicEnrichmentService);
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/AskerDataProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/AskerDataProviderTest.java
index 912322dc7..18c19df85 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/AskerDataProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/AskerDataProviderTest.java
@@ -9,11 +9,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_WITH_SESSIONS;
 import static org.hibernate.validator.internal.util.CollectionHelper.asSet;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
@@ -37,15 +33,15 @@
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
-public class AskerDataProviderTest {
+@ExtendWith(MockitoExtension.class)
+class AskerDataProviderTest {
 
   @InjectMocks private AskerDataProvider askerDataProvider;
 
@@ -62,8 +58,7 @@ public class AskerDataProviderTest {
   @Mock EmailNotificationMapper emailNotificationMapper;
 
   @Test
-  public void
-      retrieveData_Should_ReturnUserDataWithAgency_When_ProvidedWithUserWithAgencyInSession() {
+  void retrieveData_Should_ReturnUserDataWithAgency_When_ProvidedWithUserWithAgencyInSession() {
     givenAnEmailDummySuffixConfig();
     when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
     when(agencyService.getAgencies(Mockito.anyList()))
@@ -84,7 +79,7 @@ public class AskerDataProviderTest {
   }
 
   @Test
-  public void retrieveData_Should_ReturnUserDataWithAgency_When_ProvidedWithUserWithAgencies() {
+  void retrieveData_Should_ReturnUserDataWithAgency_When_ProvidedWithUserWithAgencies() {
     givenAnEmailDummySuffixConfig();
     when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
     when(agencyService.getAgencies(Mockito.anyList()))
@@ -104,20 +99,23 @@ public void retrieveData_Should_ReturnUserDataWithAgency_When_ProvidedWithUserWi
     assertEquals(AGENCY_DTO_KREUZBUND, agency);
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       retrieveData_GetConsultingTypes_Should_ThrowInternalServerErrorException_When_AgencyServiceHelperFails() {
-    givenAnEmailDummySuffixConfig();
-    when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
-    when(agencyService.getAgencies(Mockito.anyList()))
-        .thenThrow(new InternalServerErrorException(""));
-
-    askerDataProvider.retrieveData(USER);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          givenAnEmailDummySuffixConfig();
+          when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
+          when(agencyService.getAgencies(Mockito.anyList()))
+              .thenThrow(new InternalServerErrorException(""));
+
+          askerDataProvider.retrieveData(USER);
+        });
   }
 
   @Test
-  public void
-      retrieveData_Should_ReturnUserDataResponseDTOWithValidEmail_When_ProvidedWithValidUser() {
+  void retrieveData_Should_ReturnUserDataResponseDTOWithValidEmail_When_ProvidedWithValidUser() {
     givenAnEmailDummySuffixConfig();
     when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
     when(consultingTypeManager.getAllConsultingTypeIds())
@@ -130,7 +128,7 @@ public void retrieveData_Should_ReturnUserDataWithAgency_When_ProvidedWithUserWi
   }
 
   @Test
-  public void retrieveData_Should_ReturnUserDataResponseDTOWithoutEmail_When_UserHasDummyMail() {
+  void retrieveData_Should_ReturnUserDataResponseDTOWithoutEmail_When_UserHasDummyMail() {
     givenAnEmailDummySuffixConfig();
     when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
     User user = mock(User.class);
@@ -145,7 +143,7 @@ public void retrieveData_Should_ReturnUserDataResponseDTOWithoutEmail_When_UserH
   }
 
   @Test
-  public void retrieveData_Should_ReturnValidData() {
+  void retrieveData_Should_ReturnValidData() {
     givenAnEmailDummySuffixConfig();
     when(agencyService.getAgencies(any())).thenReturn(Collections.singletonList(AGENCY_DTO_SUCHT));
     LinkedHashMap<String, Object> sessionData = new LinkedHashMap<>();
@@ -184,7 +182,7 @@ public void retrieveData_Should_ReturnValidData() {
   }
 
   @Test
-  public void retrieveData_Should_ReturnUserDataWithoutAgency_When_userHasNotAgencyInSession() {
+  void retrieveData_Should_ReturnUserDataWithoutAgency_When_userHasNotAgencyInSession() {
     givenAnEmailDummySuffixConfig();
 
     User user = new EasyRandom().nextObject(User.class);
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataFacadeTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataFacadeTest.java
index c44fd9eff..3ddc5dc95 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataFacadeTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataFacadeTest.java
@@ -8,9 +8,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.GROUP_SESSION_RESPONSE_DTO;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.MESSAGE;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_SESSION_RESPONSE_DTO;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotEquals;
-import static org.junit.Assert.assertNull;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -27,15 +25,15 @@
 import java.util.Map;
 import java.util.Optional;
 import org.apache.commons.lang3.RandomStringUtils;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantDataFacadeTest {
 
   @InjectMocks private ConsultantDataFacade consultantDataFacade;
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataProviderIT.java b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataProviderIT.java
index 50244d549..e01232f3a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataProviderIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataProviderIT.java
@@ -1,8 +1,6 @@
 package de.caritas.cob.userservice.api.facade.userdata;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.Mockito.when;
@@ -21,17 +19,14 @@
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
 import org.jetbrains.annotations.NotNull;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataProviderTest.java
index fa678472f..d5f311f47 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/ConsultantDataProviderTest.java
@@ -6,11 +6,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.hibernate.validator.internal.util.CollectionHelper.asSet;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.Mockito.when;
@@ -32,14 +28,14 @@
 import java.util.Set;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantDataProviderTest {
 
   private final EasyRandom easyRandom = new EasyRandom();
@@ -56,12 +52,16 @@ public class ConsultantDataProviderTest {
 
   @Mock private EmailNotificationMapper emailNotificationMapper;
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void retrieveData_Should_ThrowInternalServerErrorException_When_NoAgenciesFound() {
-    Consultant consultant = Mockito.mock(Consultant.class);
-    when(consultant.getConsultantAgencies()).thenReturn(new HashSet<>());
-
-    underTest.retrieveData(consultant);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          Consultant consultant = Mockito.mock(Consultant.class);
+          when(consultant.getConsultantAgencies()).thenReturn(new HashSet<>());
+
+          underTest.retrieveData(consultant);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/KeycloakUserDataProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/KeycloakUserDataProviderTest.java
index 039264630..99ffd9920 100644
--- a/src/test/java/de/caritas/cob/userservice/api/facade/userdata/KeycloakUserDataProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/facade/userdata/KeycloakUserDataProviderTest.java
@@ -1,7 +1,7 @@
 package de.caritas.cob.userservice.api.facade.userdata;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import de.caritas.cob.userservice.api.adapters.keycloak.KeycloakService;
 import de.caritas.cob.userservice.api.adapters.web.dto.UserDataResponseDTO;
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/AgencyVerifierTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/AgencyVerifierTest.java
index 767aab6b6..2e9f2da9f 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/AgencyVerifierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/AgencyVerifierTest.java
@@ -4,9 +4,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.AGENCY_ID;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTING_TYPE_ID_KREUZBUND;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.CONSULTING_TYPE_ID_SUCHT;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.when;
 
@@ -16,14 +14,14 @@
 import de.caritas.cob.userservice.api.exception.httpresponses.InternalServerErrorException;
 import de.caritas.cob.userservice.api.service.agency.AgencyService;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
-public class AgencyVerifierTest {
+@ExtendWith(SpringExtension.class)
+class AgencyVerifierTest {
 
   @InjectMocks private AgencyVerifier agencyVerifier;
 
@@ -32,8 +30,7 @@ public class AgencyVerifierTest {
   private final EasyRandom easyRandom = new EasyRandom();
 
   @Test
-  public void
-      getVerifiedAgency_Should_ThrowInternalServerErrorException_When_AgencyServiceHelperFails() {
+  void getVerifiedAgency_Should_ThrowInternalServerErrorException_When_AgencyServiceHelperFails() {
     when(agencyService.getAgencyWithoutCaching(AGENCY_ID))
         .thenThrow(new InternalServerErrorException(""));
 
@@ -41,12 +38,12 @@ public class AgencyVerifierTest {
       agencyVerifier.getVerifiedAgency(AGENCY_ID, 0);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException serviceException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
   @Test
-  public void
+  void
       getVerifiedAgency_Should_ThrowBadRequestException_When_AgencyIsNotAssignedToGivenConsultingType() {
     when(agencyService.getAgencyWithoutCaching(AGENCY_ID)).thenReturn(AGENCY_DTO_SUCHT);
 
@@ -54,30 +51,34 @@ public class AgencyVerifierTest {
       agencyVerifier.getVerifiedAgency(AGENCY_ID, 15);
       fail("Expected exception: BadRequestException");
     } catch (BadRequestException badRequestException) {
-      assertTrue("Excepted BadRequestException thrown", true);
+      assertTrue(true, "Excepted BadRequestException thrown");
     }
   }
 
   @Test
-  public void getVerifiedAgency_Should_ReturnCorrectAgency_When_AgencyIsFoundAndValid() {
+  void getVerifiedAgency_Should_ReturnCorrectAgency_When_AgencyIsFoundAndValid() {
     when(agencyService.getAgencyWithoutCaching(AGENCY_ID)).thenReturn(AGENCY_DTO_SUCHT);
     AgencyDTO agency = agencyVerifier.getVerifiedAgency(AGENCY_ID, 0);
 
     assertEquals(AGENCY_ID, agency.getId());
   }
 
-  @Test(expected = BadRequestException.class)
-  public void
+  @Test
+  void
       checkIfConsultingTypeMatchesToAgency_Should_ThrowBadRequestException_When_ConsultingTypeDoesNotMatchToAgency() {
-    when(agencyService.getAgencyWithoutCaching(any())).thenReturn(AGENCY_DTO_SUCHT);
-
-    UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
-    userDTO.setConsultingType(String.valueOf(CONSULTING_TYPE_ID_KREUZBUND));
-    agencyVerifier.checkIfConsultingTypeMatchesToAgency(userDTO);
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          when(agencyService.getAgencyWithoutCaching(any())).thenReturn(AGENCY_DTO_SUCHT);
+
+          UserDTO userDTO = easyRandom.nextObject(UserDTO.class);
+          userDTO.setConsultingType(String.valueOf(CONSULTING_TYPE_ID_KREUZBUND));
+          agencyVerifier.checkIfConsultingTypeMatchesToAgency(userDTO);
+        });
   }
 
   @Test
-  public void
+  void
       checkIfConsultingTypeMatchesToAgency_ShouldNot_ThrowException_When_ConsultingTypeMatchesToAgency() {
     when(agencyService.getAgencyWithoutCaching(any())).thenReturn(AGENCY_DTO_SUCHT);
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/AuthenticatedUserTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/AuthenticatedUserTest.java
index f092de35b..66edf2e89 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/AuthenticatedUserTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/AuthenticatedUserTest.java
@@ -1,36 +1,54 @@
 package de.caritas.cob.userservice.api.helper;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
-@RunWith(MockitoJUnitRunner.class)
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+@ExtendWith(MockitoExtension.class)
 public class AuthenticatedUserTest {
 
-  @Test(expected = NullPointerException.class)
+  @Test
   public void AuthenticatedUser_Should_ThrowNullPointerExceptionWhenArgumentsAreNull()
       throws Exception {
-    new AuthenticatedUser(null, null, null, null, null);
+    assertThrows(
+        NullPointerException.class,
+        () -> {
+          new AuthenticatedUser(null, null, null, null, null);
+        });
   }
 
-  @Test(expected = NullPointerException.class)
+  @Test
   public void AuthenticatedUser_Should_ThrowNullPointerExceptionWhenUserIdIsNull()
       throws Exception {
-    AuthenticatedUser authenticatedUser = new AuthenticatedUser();
-    authenticatedUser.setUserId(null);
+    assertThrows(
+        NullPointerException.class,
+        () -> {
+          AuthenticatedUser authenticatedUser = new AuthenticatedUser();
+          authenticatedUser.setUserId(null);
+        });
   }
 
-  @Test(expected = NullPointerException.class)
+  @Test
   public void AuthenticatedUser_Should_ThrowNullPointerExceptionWhenUsernameIsNull()
       throws Exception {
-    AuthenticatedUser authenticatedUser = new AuthenticatedUser();
-    authenticatedUser.setUsername(null);
+    assertThrows(
+        NullPointerException.class,
+        () -> {
+          AuthenticatedUser authenticatedUser = new AuthenticatedUser();
+          authenticatedUser.setUsername(null);
+        });
   }
 
-  @Test(expected = NullPointerException.class)
+  @Test
   public void AuthenticatedUser_Should_ThrowNullPointerExceptionWhenAccessTokenIsNull()
       throws Exception {
-    AuthenticatedUser authenticatedUser = new AuthenticatedUser();
-    authenticatedUser.setAccessToken(null);
+    assertThrows(
+        NullPointerException.class,
+        () -> {
+          AuthenticatedUser authenticatedUser = new AuthenticatedUser();
+          authenticatedUser.setAccessToken(null);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/ChatPermissionVerifierTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/ChatPermissionVerifierTest.java
index 64f602df3..270b143a3 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/ChatPermissionVerifierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/ChatPermissionVerifierTest.java
@@ -5,9 +5,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.AGENCY_ID_2;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.AGENCY_ID_3;
 import static org.hibernate.validator.internal.util.CollectionHelper.asSet;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.config.auth.UserRole;
@@ -26,14 +24,14 @@
 import java.util.HashSet;
 import java.util.Optional;
 import java.util.Set;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
-public class ChatPermissionVerifierTest {
+@ExtendWith(MockitoExtension.class)
+class ChatPermissionVerifierTest {
 
   @InjectMocks private ChatPermissionVerifier chatPermissionVerifier;
 
@@ -50,7 +48,7 @@ public class ChatPermissionVerifierTest {
   @Mock private User user;
 
   @Test
-  public void hasSameAgencyAssigned_Should_ReturnTrue_When_ChatAgenciesContainConsultantAgency() {
+  void hasSameAgencyAssigned_Should_ReturnTrue_When_ChatAgenciesContainConsultantAgency() {
     ChatAgency[] chatAgencyArray = new ChatAgency[] {new ChatAgency(chat, AGENCY_ID_2)};
     Set<ChatAgency> chatAgencySet = new HashSet<>(Arrays.asList(chatAgencyArray));
 
@@ -71,7 +69,7 @@ AGENCY_ID_2, consultant, AGENCY_ID_2, nowInUtc(), nowInUtc(), nowInUtc(), null,
   }
 
   @Test
-  public void
+  void
       hasSameAgencyAssigned_Should_ReturnFalse_When_ChatAgenciesNotContainConsultantAgency() {
     ConsultantAgency[] consultantAgencyArray =
         new ConsultantAgency[] {
@@ -88,7 +86,7 @@ AGENCY_ID_3, consultant, AGENCY_ID_3, nowInUtc(), nowInUtc(), nowInUtc(), null,
   }
 
   @Test
-  public void hasSameAgencyAssigned_Should_ReturnTrue_When_ChatAgenciesContainUserAgency() {
+  void hasSameAgencyAssigned_Should_ReturnTrue_When_ChatAgenciesContainUserAgency() {
     ChatAgency[] chatAgencyArray = new ChatAgency[] {new ChatAgency(chat, AGENCY_ID_2)};
     Set<ChatAgency> chatAgencySet = new HashSet<>(Arrays.asList(chatAgencyArray));
 
@@ -107,7 +105,7 @@ public void hasSameAgencyAssigned_Should_ReturnTrue_When_ChatAgenciesContainUser
   }
 
   @Test
-  public void hasSameAgencyAssigned_Should_ReturnFalse_When_ChatAgenciesNotContainUserAgency() {
+  void hasSameAgencyAssigned_Should_ReturnFalse_When_ChatAgenciesNotContainUserAgency() {
     UserAgency[] userAgencyArray =
         new UserAgency[] {
           new UserAgency(AGENCY_ID, user, AGENCY_ID, null, null),
@@ -121,14 +119,14 @@ public void hasSameAgencyAssigned_Should_ReturnFalse_When_ChatAgenciesNotContain
   }
 
   @Test
-  public void hasSameAgencyAssigned_Should_ReturnFalse_When_UsersChatAgenciesAreNull() {
+  void hasSameAgencyAssigned_Should_ReturnFalse_When_UsersChatAgenciesAreNull() {
     Chat chat = new Chat();
 
     assertFalse(chatPermissionVerifier.hasSameAgencyAssigned(chat, user));
   }
 
   @Test
-  public void hasChatUserAssignment_Should_ReturnTrue_When_UserHasUserChatAssignment() {
+  void hasChatUserAssignment_Should_ReturnTrue_When_UserHasUserChatAssignment() {
     Chat chat = new Chat();
     UserChat userChat = UserChat.builder().chat(chat).user(user).build();
     chat.setChatUsers(Set.of(userChat));
@@ -137,7 +135,7 @@ public void hasChatUserAssignment_Should_ReturnTrue_When_UserHasUserChatAssignme
   }
 
   @Test
-  public void hasChatUserAssignment_Should_ReturnFalse_When_UserHasNoUserChatAssignment() {
+  void hasChatUserAssignment_Should_ReturnFalse_When_UserHasNoUserChatAssignment() {
     Chat chat = new Chat();
     UserChat userChat = UserChat.builder().chat(chat).user(new User()).build();
     chat.setChatUsers(Set.of(userChat));
@@ -146,14 +144,14 @@ public void hasChatUserAssignment_Should_ReturnFalse_When_UserHasNoUserChatAssig
   }
 
   @Test
-  public void hasChatUserAssignment_Should_ReturnFalse_When_UsersChatUsersAreNull() {
+  void hasChatUserAssignment_Should_ReturnFalse_When_UsersChatUsersAreNull() {
     Chat chat = new Chat();
 
     assertFalse(chatPermissionVerifier.hasChatUserAssignment(chat, user));
   }
 
   @Test
-  public void
+  void
       verifyPermissionForChat_Should_verifyConsultantPermission_When_ChatAgenciesContainConsultantAgency() {
     Consultant consultant = new Consultant();
     ConsultantAgency consultantAgency = new ConsultantAgency();
@@ -170,36 +168,44 @@ public void hasChatUserAssignment_Should_ReturnFalse_When_UsersChatUsersAreNull(
     assertDoesNotThrow(() -> this.chatPermissionVerifier.verifyPermissionForChat(chat));
   }
 
-  @Test(expected = NotFoundException.class)
-  public void
+  @Test
+  void
       verifyPermissionForChat_Should_throwNotFoundException_When_consultantDoesNotExistInDatabase() {
-    when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.CONSULTANT.getValue()));
-    when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
-        .thenReturn(Optional.empty());
-
-    this.chatPermissionVerifier.verifyPermissionForChat(chat);
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.CONSULTANT.getValue()));
+          when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
+              .thenReturn(Optional.empty());
+
+          this.chatPermissionVerifier.verifyPermissionForChat(chat);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
-  public void
+  @Test
+  void
       verifyPermissionForChat_Should_throwForbiddenException_When_agenciesOfChatAndConsultantAreDifferent() {
-    Consultant consultant = new Consultant();
-    ConsultantAgency consultantAgency = new ConsultantAgency();
-    consultantAgency.setAgencyId(1L);
-    consultant.setConsultantAgencies(asSet(consultantAgency));
-    ChatAgency chatAgency = new ChatAgency();
-    chatAgency.setAgencyId(2L);
-    Chat chat = new Chat();
-    chat.setChatAgencies(asSet(chatAgency));
-    when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.CONSULTANT.getValue()));
-    when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
-        .thenReturn(Optional.of(consultant));
-
-    this.chatPermissionVerifier.verifyPermissionForChat(chat);
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Consultant consultant = new Consultant();
+          ConsultantAgency consultantAgency = new ConsultantAgency();
+          consultantAgency.setAgencyId(1L);
+          consultant.setConsultantAgencies(asSet(consultantAgency));
+          ChatAgency chatAgency = new ChatAgency();
+          chatAgency.setAgencyId(2L);
+          Chat chat = new Chat();
+          chat.setChatAgencies(asSet(chatAgency));
+          when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.CONSULTANT.getValue()));
+          when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
+              .thenReturn(Optional.of(consultant));
+
+          this.chatPermissionVerifier.verifyPermissionForChat(chat);
+        });
   }
 
   @Test
-  public void
+  void
       verifyPermissionForChat_Should_verifyUserPermission_When_ChatAgenciesContainUserAgency() {
     User user = new User();
     UserAgency userAgency = new UserAgency();
@@ -216,7 +222,7 @@ public void hasChatUserAssignment_Should_ReturnFalse_When_UsersChatUsersAreNull(
   }
 
   @Test
-  public void verifyPermissionForChat_Should_verifyUserPermission_When_UserHasUserChatAssignment() {
+  void verifyPermissionForChat_Should_verifyUserPermission_When_UserHasUserChatAssignment() {
     UserChat userChat = UserChat.builder().chat(chat).user(user).build();
     when(chat.getChatUsers()).thenReturn(Set.of(userChat));
     when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
@@ -226,7 +232,7 @@ public void verifyPermissionForChat_Should_verifyUserPermission_When_UserHasUser
   }
 
   @Test
-  public void
+  void
       verifyCanModerateChat_Should_AllowToModerate_When_ConsultantHasAccessToSameAgencyAsChat() {
     Consultant consultant = new Consultant();
     ConsultantAgency consultantAgency = new ConsultantAgency();
@@ -242,69 +248,92 @@ public void verifyPermissionForChat_Should_verifyUserPermission_When_UserHasUser
     assertDoesNotThrow(() -> this.chatPermissionVerifier.verifyCanModerateChat(chat));
   }
 
-  @Test(expected = ForbiddenException.class)
-  public void
+  @Test
+  void
       verifyCanModerateChat_Should_Not_AllowToModerate_When_ConsultantDoesNotHaveAccessToSameAgencyAsChat() {
-    Consultant consultant = new Consultant();
-    ConsultantAgency consultantAgency = new ConsultantAgency();
-    consultantAgency.setAgencyId(2L);
-    consultant.setConsultantAgencies(asSet(consultantAgency));
-    ChatAgency chatAgency = new ChatAgency();
-    chatAgency.setAgencyId(1L);
-    Chat chat = new Chat();
-    chat.setChatAgencies(asSet(chatAgency));
-    when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.CONSULTANT.getValue()));
-    when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
-        .thenReturn(Optional.of(consultant));
-    this.chatPermissionVerifier.verifyCanModerateChat(chat);
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Consultant consultant = new Consultant();
+          ConsultantAgency consultantAgency = new ConsultantAgency();
+          consultantAgency.setAgencyId(2L);
+          consultant.setConsultantAgencies(asSet(consultantAgency));
+          ChatAgency chatAgency = new ChatAgency();
+          chatAgency.setAgencyId(1L);
+          Chat chat = new Chat();
+          chat.setChatAgencies(asSet(chatAgency));
+          when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.CONSULTANT.getValue()));
+          when(consultantService.getConsultantViaAuthenticatedUser(authenticatedUser))
+              .thenReturn(Optional.of(consultant));
+          this.chatPermissionVerifier.verifyCanModerateChat(chat);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
-  public void verifyCanModerateChat_Should_Not_AllowToModerate_When_AccessedAsUser() {
-    ChatAgency chatAgency = new ChatAgency();
-    chatAgency.setAgencyId(1L);
-    Chat chat = new Chat();
-    chat.setChatAgencies(asSet(chatAgency));
-    when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
-    this.chatPermissionVerifier.verifyCanModerateChat(chat);
+  @Test
+  void verifyCanModerateChat_Should_Not_AllowToModerate_When_AccessedAsUser() {
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          ChatAgency chatAgency = new ChatAgency();
+          chatAgency.setAgencyId(1L);
+          Chat chat = new Chat();
+          chat.setChatAgencies(asSet(chatAgency));
+          when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
+          this.chatPermissionVerifier.verifyCanModerateChat(chat);
+        });
   }
 
-  @Test(expected = NotFoundException.class)
-  public void
+  @Test
+  void
       verifyPermissionForChat_Should_throwNotFoundException_When_UserDoesNotExistInDatabase() {
-    when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
-    when(userService.getUserViaAuthenticatedUser(authenticatedUser)).thenReturn(Optional.empty());
-
-    this.chatPermissionVerifier.verifyPermissionForChat(chat);
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
+          when(userService.getUserViaAuthenticatedUser(authenticatedUser))
+              .thenReturn(Optional.empty());
+
+          this.chatPermissionVerifier.verifyPermissionForChat(chat);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
-  public void
+  @Test
+  void
       verifyPermissionForChat_Should_throwForbiddenException_When_AgenciesOfChatAndUserAreDifferent() {
-    User user = new User();
-    UserAgency userAgency = new UserAgency();
-    userAgency.setAgencyId(1L);
-    user.setUserAgencies(asSet(userAgency));
-    ChatAgency chatAgency = new ChatAgency();
-    chatAgency.setAgencyId(2L);
-    Chat chat = new Chat();
-    chat.setChatAgencies(asSet(chatAgency));
-    when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
-    when(userService.getUserViaAuthenticatedUser(authenticatedUser)).thenReturn(Optional.of(user));
-
-    this.chatPermissionVerifier.verifyPermissionForChat(chat);
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          User user = new User();
+          UserAgency userAgency = new UserAgency();
+          userAgency.setAgencyId(1L);
+          user.setUserAgencies(asSet(userAgency));
+          ChatAgency chatAgency = new ChatAgency();
+          chatAgency.setAgencyId(2L);
+          Chat chat = new Chat();
+          chat.setChatAgencies(asSet(chatAgency));
+          when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
+          when(userService.getUserViaAuthenticatedUser(authenticatedUser))
+              .thenReturn(Optional.of(user));
+
+          this.chatPermissionVerifier.verifyPermissionForChat(chat);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
-  public void
+  @Test
+  void
       verifyPermissionForChat_Should_throwForbiddenException_When_UserHasNoChatUserAssignment() {
-    Chat chat = new Chat();
-    UserChat userChat = UserChat.builder().user(new User()).chat(chat).build();
-    chat.setChatUsers(Set.of(userChat));
-
-    when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
-    when(userService.getUserViaAuthenticatedUser(authenticatedUser)).thenReturn(Optional.of(user));
-
-    this.chatPermissionVerifier.verifyPermissionForChat(chat);
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Chat chat = new Chat();
+          UserChat userChat = UserChat.builder().user(new User()).chat(chat).build();
+          chat.setChatUsers(Set.of(userChat));
+
+          when(authenticatedUser.getRoles()).thenReturn(asSet(UserRole.USER.getValue()));
+          when(userService.getUserViaAuthenticatedUser(authenticatedUser))
+              .thenReturn(Optional.of(user));
+
+          this.chatPermissionVerifier.verifyPermissionForChat(chat);
+        });
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/EmptyObjectSerializerTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/EmptyObjectSerializerTest.java
index 5cf5541f7..160e75a6c 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/EmptyObjectSerializerTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/EmptyObjectSerializerTest.java
@@ -1,15 +1,15 @@
 package de.caritas.cob.userservice.api.helper;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import de.caritas.cob.userservice.api.adapters.rocketchat.dto.login.LdapLoginDTO;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class EmptyObjectSerializerTest {
 
   private final String USERNAME = "username";
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/HelperTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/HelperTest.java
index 956df3b88..632151e01 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/HelperTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/HelperTest.java
@@ -3,16 +3,16 @@
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
 
 import java.util.Date;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class HelperTest {
 
   private static String TEXT = "Lorem Ipsum";
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/RocketChatRoomNameGeneratorTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/RocketChatRoomNameGeneratorTest.java
index 10d258dd3..eaac86de7 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/RocketChatRoomNameGeneratorTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/RocketChatRoomNameGeneratorTest.java
@@ -4,19 +4,19 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.SESSION;
 import static org.hamcrest.CoreMatchers.startsWith;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocketChatRoomNameGeneratorTest {
 
   private RocketChatRoomNameGenerator rocketChatRoomNameGenerator;
 
-  @Before
+  @BeforeEach
   public void setup() {
     this.rocketChatRoomNameGenerator = new RocketChatRoomNameGenerator();
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/SessionDataProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/SessionDataProviderTest.java
index 95088a112..f117bfd2b 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/SessionDataProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/SessionDataProviderTest.java
@@ -18,11 +18,7 @@
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hamcrest.Matchers.nullValue;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.when;
 
 import com.neovisionaries.i18n.LanguageCode;
@@ -44,13 +40,13 @@
 import java.util.List;
 import java.util.Map;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class SessionDataProviderTest {
 
   private SessionDataProvider sessionDataProvider;
@@ -186,7 +182,7 @@ public class SessionDataProviderTest {
               .roles(null)
               .registration(null);
 
-  @Before
+  @BeforeEach
   public void setup() {
     consultingTypeManager = Mockito.mock(ConsultingTypeManager.class);
     sessionDataProvider = new SessionDataProvider(consultingTypeManager);
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/SessionListAnalyserTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/SessionListAnalyserTest.java
index 238ae7f63..066e4371d 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/SessionListAnalyserTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/SessionListAnalyserTest.java
@@ -12,9 +12,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.ROOMS_LAST_MESSAGE_DTO_2;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.ROOMS_LAST_MESSAGE_DTO_MAP;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.ROOMS_LAST_MESSAGE_DTO_WITHOUT_ATTACHMENT;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.atLeastOnce;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -22,13 +20,13 @@
 import de.caritas.cob.userservice.api.adapters.web.dto.SessionAttachmentDTO;
 import de.caritas.cob.userservice.api.exception.CustomCryptoException;
 import de.caritas.cob.userservice.api.service.DecryptionService;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class SessionListAnalyserTest {
 
   @InjectMocks private SessionListAnalyser sessionListAnalyser;
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/UserHelperTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/UserHelperTest.java
index f4a247ee1..2d39487fc 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/UserHelperTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/UserHelperTest.java
@@ -9,24 +9,25 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERNAME_TOO_SHORT;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_ID;
 import static org.apache.commons.lang3.RandomStringUtils.randomAlphabetic;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.when;
 import static org.springframework.test.util.ReflectionTestUtils.setField;
 
 import de.caritas.cob.userservice.api.port.out.IdentityClientConfig;
 import java.util.List;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 
-@RunWith(MockitoJUnitRunner.class)
-public class UserHelperTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class UserHelperTest {
 
   private static final EasyRandom easyRandom = new EasyRandom();
   private final UsernameTranscoder usernameTranscoder = new UsernameTranscoder();
@@ -34,38 +35,38 @@ public class UserHelperTest {
   @InjectMocks private UserHelper userHelper;
   @Mock private IdentityClientConfig identityClientConfig;
 
-  @Before
-  public void setup() throws NoSuchFieldException, SecurityException {
+  @BeforeEach
+  void setup() throws NoSuchFieldException, SecurityException {
     when(identityClientConfig.getEmailDummySuffix()).thenReturn(FIELD_VALUE_EMAIL_DUMMY_SUFFIX);
     setField(userHelper, "usernameTranscoder", usernameTranscoder);
   }
 
   @Test
-  public void isUsernameValid_Should_ReturnFalse_WhenUsernameIsTooShort() {
+  void isUsernameValid_Should_ReturnFalse_WhenUsernameIsTooShort() {
     assertFalse(userHelper.isUsernameValid(USERNAME_TOO_SHORT));
   }
 
   @Test
-  public void isUsernameValid_Should_ReturnFalse_WhenUsernameIsTooLong() {
+  void isUsernameValid_Should_ReturnFalse_WhenUsernameIsTooLong() {
     assertFalse(userHelper.isUsernameValid(USERNAME_TOO_LONG));
   }
 
   @Test
-  public void isValidEmailShouldReturnTrueOnValidAddress() {
+  void isValidEmailShouldReturnTrueOnValidAddress() {
     var emailAddress = givenARandomEmail();
 
     assertTrue(userHelper.isValidEmail(emailAddress));
   }
 
   @Test
-  public void isValidEmailShouldReturnTrueOnAddressWithUmlaut() {
+  void isValidEmailShouldReturnTrueOnAddressWithUmlaut() {
     var emailAddress = givenARandomEmailWithAnUmlaut();
 
     assertTrue(userHelper.isValidEmail(emailAddress));
   }
 
   @Test
-  public void isValidEmailShouldReturnFalseOnEmptyAddress() {
+  void isValidEmailShouldReturnFalseOnEmptyAddress() {
     assertFalse(userHelper.isValidEmail(null));
     assertFalse(userHelper.isValidEmail(""));
     assertFalse(userHelper.isValidEmail("@"));
@@ -74,37 +75,37 @@ public void isValidEmailShouldReturnFalseOnEmptyAddress() {
   }
 
   @Test
-  public void getDummyEmail_Should_ReturnRcUserIdWithDummyEmailSuffix() {
+  void getDummyEmail_Should_ReturnRcUserIdWithDummyEmailSuffix() {
     assertEquals(USER_ID + FIELD_VALUE_EMAIL_DUMMY_SUFFIX, userHelper.getDummyEmail(USER_ID));
   }
 
   @Test
-  public void doUsernamesMatch_Should_ReturnFalse_WhenDecodedUsernamesDontMatch() {
+  void doUsernamesMatch_Should_ReturnFalse_WhenDecodedUsernamesDontMatch() {
     assertFalse(userHelper.doUsernamesMatch(USERNAME_CONSULTANT_DECODED, USERNAME_DECODED));
   }
 
   @Test
-  public void doUsernamesMatch_Should_ReturnFalse_WhenEncodedUsernamesDontMatch() {
+  void doUsernamesMatch_Should_ReturnFalse_WhenEncodedUsernamesDontMatch() {
     assertFalse(userHelper.doUsernamesMatch(USERNAME_CONSULTANT_ENCODED, USERNAME_ENCODED));
   }
 
   @Test
-  public void doUsernamesMatch_Should_ReturnFalse_WhenEncodedAndDecodedUsernamesDontMatch() {
+  void doUsernamesMatch_Should_ReturnFalse_WhenEncodedAndDecodedUsernamesDontMatch() {
     assertFalse(userHelper.doUsernamesMatch(USERNAME_CONSULTANT_ENCODED, USERNAME_DECODED));
   }
 
   @Test
-  public void doUsernamesMatch_Should_ReturnTrue_WhenDecodedUsernamesMatch() {
+  void doUsernamesMatch_Should_ReturnTrue_WhenDecodedUsernamesMatch() {
     assertTrue(userHelper.doUsernamesMatch(USERNAME_DECODED, USERNAME_DECODED));
   }
 
   @Test
-  public void doUsernamesMatch_Should_ReturnTrue_WhenEncodedUsernamesMatch() {
+  void doUsernamesMatch_Should_ReturnTrue_WhenEncodedUsernamesMatch() {
     assertTrue(userHelper.doUsernamesMatch(USERNAME_ENCODED, USERNAME_ENCODED));
   }
 
   @Test
-  public void doUsernamesMatch_Should_ReturnTrue_WhenEncodedAndDecodedUsernamesMatch() {
+  void doUsernamesMatch_Should_ReturnTrue_WhenEncodedAndDecodedUsernamesMatch() {
     assertTrue(userHelper.doUsernamesMatch(USERNAME_ENCODED, USERNAME_DECODED));
   }
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/UserVerifierTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/UserVerifierTest.java
index 378644057..ac33e3cfc 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/UserVerifierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/UserVerifierTest.java
@@ -2,8 +2,8 @@
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.adapters.keycloak.KeycloakService;
diff --git a/src/test/java/de/caritas/cob/userservice/api/helper/UsernameTranscoderTest.java b/src/test/java/de/caritas/cob/userservice/api/helper/UsernameTranscoderTest.java
index 2dc376ba3..5a449b632 100644
--- a/src/test/java/de/caritas/cob/userservice/api/helper/UsernameTranscoderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/helper/UsernameTranscoderTest.java
@@ -2,9 +2,9 @@
 
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERNAME_DECODED;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERNAME_ENCODED;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class UsernameTranscoderTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/manager/consultingtype/ConsultingTypeManagerTest.java b/src/test/java/de/caritas/cob/userservice/api/manager/consultingtype/ConsultingTypeManagerTest.java
index 6da802b9e..0ca72b466 100644
--- a/src/test/java/de/caritas/cob/userservice/api/manager/consultingtype/ConsultingTypeManagerTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/manager/consultingtype/ConsultingTypeManagerTest.java
@@ -1,9 +1,6 @@
 package de.caritas.cob.userservice.api.manager.consultingtype;
 
-import static org.junit.Assert.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.Mockito.when;
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/model/ChatAgencyTest.java b/src/test/java/de/caritas/cob/userservice/api/model/ChatAgencyTest.java
index dcf055322..2f1df5510 100644
--- a/src/test/java/de/caritas/cob/userservice/api/model/ChatAgencyTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/model/ChatAgencyTest.java
@@ -4,7 +4,7 @@
 import static org.hamcrest.Matchers.is;
 
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class ChatAgencyTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/model/ChatTest.java b/src/test/java/de/caritas/cob/userservice/api/model/ChatTest.java
index 9b329d826..37236ad33 100644
--- a/src/test/java/de/caritas/cob/userservice/api/model/ChatTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/model/ChatTest.java
@@ -3,10 +3,11 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import de.caritas.cob.userservice.api.exception.httpresponses.InternalServerErrorException;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class ChatTest {
 
@@ -52,12 +53,16 @@ public void equals_Should_returnTrue_When_sessionIdsAreEqual() {
     assertThat(equals, is(true));
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void nextDateShouldThrowExceptionWhenChatIsRepetitiveButNoStartDate() {
-    var chat = new Chat();
-    chat.setRepetitive(true);
-
-    chat.nextStart();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          var chat = new Chat();
+          chat.setRepetitive(true);
+
+          chat.nextStart();
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/model/ConsultantAgencyTest.java b/src/test/java/de/caritas/cob/userservice/api/model/ConsultantAgencyTest.java
index 191b93761..d963f81cb 100644
--- a/src/test/java/de/caritas/cob/userservice/api/model/ConsultantAgencyTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/model/ConsultantAgencyTest.java
@@ -4,7 +4,7 @@
 import static org.hamcrest.Matchers.is;
 
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class ConsultantAgencyTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/model/ConsultantTest.java b/src/test/java/de/caritas/cob/userservice/api/model/ConsultantTest.java
index dfda9cf2f..71bb565ed 100644
--- a/src/test/java/de/caritas/cob/userservice/api/model/ConsultantTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/model/ConsultantTest.java
@@ -2,15 +2,15 @@
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import com.neovisionaries.i18n.LanguageCode;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantTest {
 
   private static final String FIRSTNAME = "firstname";
diff --git a/src/test/java/de/caritas/cob/userservice/api/model/SessionDataTest.java b/src/test/java/de/caritas/cob/userservice/api/model/SessionDataTest.java
index 49b7527e4..630231053 100644
--- a/src/test/java/de/caritas/cob/userservice/api/model/SessionDataTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/model/SessionDataTest.java
@@ -4,7 +4,7 @@
 import static org.hamcrest.Matchers.is;
 
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class SessionDataTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/model/SessionTest.java b/src/test/java/de/caritas/cob/userservice/api/model/SessionTest.java
index 1173ac90f..e56c276bd 100644
--- a/src/test/java/de/caritas/cob/userservice/api/model/SessionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/model/SessionTest.java
@@ -4,7 +4,7 @@
 import static org.hamcrest.Matchers.is;
 
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class SessionTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/model/UserAgencyTest.java b/src/test/java/de/caritas/cob/userservice/api/model/UserAgencyTest.java
index c876109af..cd5bdcec5 100644
--- a/src/test/java/de/caritas/cob/userservice/api/model/UserAgencyTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/model/UserAgencyTest.java
@@ -4,7 +4,7 @@
 import static org.hamcrest.Matchers.is;
 
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class UserAgencyTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/model/UserTest.java b/src/test/java/de/caritas/cob/userservice/api/model/UserTest.java
index 3b0643334..06825c4c9 100644
--- a/src/test/java/de/caritas/cob/userservice/api/model/UserTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/model/UserTest.java
@@ -4,7 +4,7 @@
 import static org.hamcrest.Matchers.is;
 
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class UserTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/ChatServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/ChatServiceTest.java
index edd787836..05d925f37 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/ChatServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/ChatServiceTest.java
@@ -17,11 +17,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -45,18 +41,18 @@
 import java.time.LocalTime;
 import java.util.List;
 import java.util.Optional;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
-public class ChatServiceTest {
+@ExtendWith(MockitoExtension.class)
+class ChatServiceTest {
 
   @InjectMocks private ChatService chatService;
 
@@ -72,13 +68,13 @@ public class ChatServiceTest {
 
   @Mock private AgencyService agencyService;
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void setup() {
     setInternalState(LogService.class, "LOGGER", logger);
   }
 
   @Test
-  public void getChatsForUserId_Should_CallFindByUserIdAndFindAssignedByUserIdOnChatRepository() {
+  void getChatsForUserId_Should_CallFindByUserIdAndFindAssignedByUserIdOnChatRepository() {
     chatService.getChatsForUserId(USER_ID);
 
     verify(chatRepository).findByUserId(USER_ID);
@@ -86,7 +82,7 @@ public void getChatsForUserId_Should_CallFindByUserIdAndFindAssignedByUserIdOnCh
   }
 
   @Test
-  public void getChatsForUserId_Should_ConcatChatsAndAssignedChats() {
+  void getChatsForUserId_Should_ConcatChatsAndAssignedChats() {
     when(chatRepository.findByUserId(USER_ID)).thenReturn(singletonList(ACTIVE_CHAT));
     when(chatRepository.findAssignedByUserId(USER_ID)).thenReturn(singletonList(CHAT_V2));
 
@@ -96,7 +92,7 @@ public void getChatsForUserId_Should_ConcatChatsAndAssignedChats() {
   }
 
   @Test
-  public void getChatsForUserId_Should_ReturnListOfUserSessionResponseDTOWithChats() {
+  void getChatsForUserId_Should_ReturnListOfUserSessionResponseDTOWithChats() {
     when(chatRepository.findByUserId(USER_ID)).thenReturn(singletonList(ACTIVE_CHAT));
     when(consultantService.findConsultantsByAgencyIds(Mockito.any()))
         .thenReturn(singletonList(CONSULTANT));
@@ -130,7 +126,7 @@ public void getChatsForUserId_Should_ReturnListOfUserSessionResponseDTOWithChats
   }
 
   @Test
-  public void
+  void
       getChatsForUserId_Should_ReturnListOfUserSessionResponseDTOWithChats_When_AssignedChatIsFound() {
     when(chatRepository.findAssignedByUserId(USER_ID)).thenReturn(singletonList(CHAT_V2));
     when(consultantService.findConsultantsByAgencyIds(Mockito.any()))
@@ -177,7 +173,7 @@ public void getChatsForUserId_Should_ReturnListOfUserSessionResponseDTOWithChats
   }
 
   @Test
-  public void getChatsForConsultant_Should_ReturnListOfConsultantSessionResponseDTOWithChats() {
+  void getChatsForConsultant_Should_ReturnListOfConsultantSessionResponseDTOWithChats() {
     Consultant consultant = Mockito.mock(Consultant.class);
 
     when(chatRepository.findByAgencyIds(Mockito.any())).thenReturn(singletonList(ACTIVE_CHAT));
@@ -213,7 +209,7 @@ public void getChatsForConsultant_Should_ReturnListOfConsultantSessionResponseDT
   }
 
   @Test
-  public void getChatsForConsultant_Should_ReturnEmptyListWhenListOfChatsIsEmpty() {
+  void getChatsForConsultant_Should_ReturnEmptyListWhenListOfChatsIsEmpty() {
     Consultant consultant = Mockito.mock(Consultant.class);
 
     List<ConsultantSessionResponseDTO> resultList = chatService.getChatsForConsultant(consultant);
@@ -222,7 +218,7 @@ public void getChatsForConsultant_Should_ReturnEmptyListWhenListOfChatsIsEmpty()
   }
 
   @Test
-  public void getChat_Should_ReturnChatObject() {
+  void getChat_Should_ReturnChatObject() {
     when(chatRepository.findById(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
 
     Optional<Chat> result = chatService.getChat(CHAT_ID);
@@ -233,7 +229,7 @@ public void getChat_Should_ReturnChatObject() {
   }
 
   @Test
-  public void getChatByGroupId_Should_ReturnChatObject() {
+  void getChatByGroupId_Should_ReturnChatObject() {
     when(chatRepository.findByGroupId(RC_GROUP_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
 
     Optional<Chat> result = chatService.getChatByGroupId(RC_GROUP_ID);
@@ -244,43 +240,43 @@ public void getChatByGroupId_Should_ReturnChatObject() {
   }
 
   @Test
-  public void updateChat_Should_ThrowBadRequestException_WhenChatDoesNotExist() {
+  void updateChat_Should_ThrowBadRequestException_WhenChatDoesNotExist() {
     when(chatRepository.findById(CHAT_ID)).thenReturn(Optional.empty());
 
     try {
       chatService.updateChat(CHAT_ID, CHAT_DTO, AUTHENTICATED_USER);
       fail("Expected exception: BadRequestException");
     } catch (BadRequestException badRequestException) {
-      assertTrue("Excepted BadRequestException thrown", true);
+      assertTrue(true, "Excepted BadRequestException thrown");
     }
   }
 
   @Test
-  public void updateChat_Should_ThrowForbiddenException_WhenCallingConsultantNotOwnerOfChat() {
+  void updateChat_Should_ThrowForbiddenException_WhenCallingConsultantNotOwnerOfChat() {
     when(chatRepository.findById(CHAT_ID)).thenReturn(Optional.of(INACTIVE_CHAT));
 
     try {
       chatService.updateChat(CHAT_ID, CHAT_DTO, AUTHENTICATED_USER_3);
       fail("Expected exception: ForbiddenException");
     } catch (ForbiddenException forbiddenException) {
-      assertTrue("Excepted ForbiddenException thrown", true);
+      assertTrue(true, "Excepted ForbiddenException thrown");
     }
   }
 
   @Test
-  public void updateChat_Should_ThrowConflictException_WhenChatIsActive() {
+  void updateChat_Should_ThrowConflictException_WhenChatIsActive() {
     when(chatRepository.findById(CHAT_ID)).thenReturn(Optional.of(ACTIVE_CHAT));
 
     try {
       chatService.updateChat(CHAT_ID, CHAT_DTO, AUTHENTICATED_USER_CONSULTANT);
       fail("Expected exception: ConflictException");
     } catch (ConflictException conflictException) {
-      assertTrue("Excepted ConflictException thrown", true);
+      assertTrue(true, "Excepted ConflictException thrown");
     }
   }
 
   @Test
-  public void updateChat_Should_SaveNewChatSettings() {
+  void updateChat_Should_SaveNewChatSettings() {
     // given
     Chat inactiveChat = new Chat();
     inactiveChat.setActive(false);
@@ -298,7 +294,7 @@ public void updateChat_Should_SaveNewChatSettings() {
   }
 
   @Test
-  public void saveChatAgencyRelation_Should_saveChatAgencyInRepository() {
+  void saveChatAgencyRelation_Should_saveChatAgencyInRepository() {
     ChatAgency chatAgency = new ChatAgency();
 
     chatService.saveChatAgencyRelation(chatAgency);
@@ -307,7 +303,7 @@ public void saveChatAgencyRelation_Should_saveChatAgencyInRepository() {
   }
 
   @Test
-  public void saveUserChatRelation_Should_saveUserChatInRepository() {
+  void saveUserChatRelation_Should_saveUserChatInRepository() {
     UserChat chatUser = new UserChat();
 
     chatService.saveUserChatRelation(chatUser);
@@ -316,7 +312,7 @@ public void saveUserChatRelation_Should_saveUserChatInRepository() {
   }
 
   @Test
-  public void deleteChat_Should_deleteChatInRepository() {
+  void deleteChat_Should_deleteChatInRepository() {
     Chat chat = new Chat();
 
     chatService.deleteChat(chat);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/ConsultantAgencyServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/ConsultantAgencyServiceTest.java
index 6acd4637b..0f5f18cc2 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/ConsultantAgencyServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/ConsultantAgencyServiceTest.java
@@ -7,9 +7,7 @@
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.hasSize;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -31,16 +29,16 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.slf4j.Logger;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class ConsultantAgencyServiceTest {
 
   private final String CONSULTANT_ID = "1b71cc46-650d-42bb-8299-f8e3f6d7249a";
@@ -105,7 +103,7 @@ public class ConsultantAgencyServiceTest {
   @SuppressWarnings("unused")
   private UserDtoMapper userDtoMapper;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(LogService.class, "LOGGER", logger);
   }
@@ -142,7 +140,7 @@ public void findConsultantsByAgencyId_Should_ReturnListOfConsultantAgency_WhenAg
       consultantAgencyService.getConsultantsOfAgency(AGENCY_ID);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException serviceException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
@@ -158,7 +156,7 @@ public void findConsultantsByAgencyId_Should_ReturnListOfConsultantAgency_WhenAg
       consultantAgencyService.getConsultantsOfAgency(AGENCY_ID);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException serviceException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/ConsultantServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/service/ConsultantServiceIT.java
index 29faa4633..453cf9178 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/ConsultantServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/ConsultantServiceIT.java
@@ -3,14 +3,11 @@
 import de.caritas.cob.userservice.api.UserServiceApplication;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
-import org.junit.runner.RunWith;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/ConsultingTypeServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/ConsultingTypeServiceTest.java
index 633cdd3aa..cc27f520c 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/ConsultingTypeServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/ConsultingTypeServiceTest.java
@@ -1,6 +1,6 @@
 package de.caritas.cob.userservice.api.service;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/DecryptionServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/DecryptionServiceTest.java
index 2d3b88da6..b206b04bb 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/DecryptionServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/DecryptionServiceTest.java
@@ -1,19 +1,17 @@
 package de.caritas.cob.userservice.api.service;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 
 import de.caritas.cob.userservice.api.exception.CustomCryptoException;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.test.util.ReflectionTestUtils;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DecryptionServiceTest {
 
   private final String KEY_MASTER = "MasterKeyTestKey";
@@ -30,7 +28,7 @@ public class DecryptionServiceTest {
 
   @Mock private LogService logService;
 
-  @Before
+  @BeforeEach
   public void setup() throws NoSuchFieldException {
     ReflectionTestUtils.setField(encryptionService, FIELD_NAME_FRAGMENT_APP_KEY, KEY_APPLICATION);
     encryptionService.updateMasterKey(KEY_MASTER);
@@ -38,24 +36,24 @@ public void setup() throws NoSuchFieldException {
 
   @Test
   public void check_setup() {
-    assertEquals("MasterKey was not properly set", KEY_MASTER, encryptionService.getMasterKey());
+    assertEquals(KEY_MASTER, encryptionService.getMasterKey(), "MasterKey was not properly set");
     assertEquals(
-        "ApplicationKey was not properly set",
         KEY_APPLICATION,
-        encryptionService.getApplicationKey());
+        encryptionService.getApplicationKey(),
+        "ApplicationKey was not properly set");
   }
 
   @Test
   public void updateMasterKey_Should_UpdateMasterKeyFragment() {
     encryptionService.updateMasterKey(KEY_MASTER);
-    assertEquals("Cannot properly set MasterKey", KEY_MASTER, encryptionService.getMasterKey());
+    assertEquals(KEY_MASTER, encryptionService.getMasterKey(), "Cannot properly set MasterKey");
   }
 
   @Test
   public void decrypt_Should_ReturnDecryptedText_WhenProvidedWithValidParameters()
       throws Exception {
     String decryptedMessage = encryptionService.decrypt(MESSAGE_ENCRYPTED, KEY_SESSION);
-    assertEquals("Did not get the expected decrypted result.", MESSAGE_PLAIN, decryptedMessage);
+    assertEquals(MESSAGE_PLAIN, decryptedMessage, "Did not get the expected decrypted result.");
   }
 
   @Test
@@ -64,7 +62,7 @@ public void decrypt_Should_ReturnWrongDecryptedText_WhenProvidedWithInvalidParam
       encryptionService.decrypt(MESSAGE_ENCRYPTED, KEY_SESSION_WRONG);
       fail("The expected BadPaddingException due to wrong password was not thrown.");
     } catch (CustomCryptoException ex) {
-      assertTrue("Expected BadPaddingException thrown", true);
+      assertTrue(true, "Expected BadPaddingException thrown");
     }
   }
 }
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/LogServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/LogServiceTest.java
index 02849e0c3..f72b87a48 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/LogServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/LogServiceTest.java
@@ -13,14 +13,14 @@
 import static org.powermock.reflect.Whitebox.setInternalState;
 
 import java.io.PrintWriter;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class LogServiceTest {
 
   private final String ERROR_MESSAGE = "Error message";
@@ -29,7 +29,7 @@ public class LogServiceTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(LogService.class, "LOGGER", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/RocketChatServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/RocketChatServiceTest.java
index f04954fef..425f78a49 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/RocketChatServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/RocketChatServiceTest.java
@@ -30,13 +30,7 @@
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
-import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
-import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
@@ -100,15 +94,17 @@
 import org.bson.Document;
 import org.bson.conversions.Bson;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.ArgumentMatchers;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 import org.slf4j.Logger;
 import org.springframework.http.HttpEntity;
 import org.springframework.http.HttpMethod;
@@ -119,8 +115,9 @@
 import org.springframework.web.client.RestClientResponseException;
 import org.springframework.web.client.RestTemplate;
 
-@RunWith(MockitoJUnitRunner.class)
-public class RocketChatServiceTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class RocketChatServiceTest {
 
   private final String MESSAGE = "Lorem Ipsum";
   private final String GROUP_ID = "xxxYYY";
@@ -195,8 +192,8 @@ public class RocketChatServiceTest {
 
   @Mock private FindIterable<Document> findIterable;
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void setup() {
     rocketChatConfig.setBaseUrl("http://localhost/api/v1");
     setField(rocketChatService, "rocketChatConfig", rocketChatConfig);
 
@@ -205,7 +202,7 @@ public void setup() {
 
   /** Method: createPrivateGroup */
   @Test
-  public void createPrivateGroup_Should_ReturnTheGroupId_WhenRocketChatApiCallWasSuccessfully()
+  void createPrivateGroup_Should_ReturnTheGroupId_WhenRocketChatApiCallWasSuccessfully()
       throws SecurityException, RocketChatCreateGroupException {
 
     when(restTemplate.postForObject(
@@ -220,7 +217,7 @@ public void createPrivateGroup_Should_ReturnTheGroupId_WhenRocketChatApiCallWasS
   }
 
   @Test
-  public void
+  void
       createPrivateGroup_Should_ThrowRocketChatCreateGroupException_WhenApiCallFailsWithAnException()
           throws SecurityException {
 
@@ -234,13 +231,13 @@ public void createPrivateGroup_Should_ReturnTheGroupId_WhenRocketChatApiCallWasS
       rocketChatService.createPrivateGroup(GROUP_NAME, RC_CREDENTIALS);
       fail("Expected exception: RocketChatCreateGroupException");
     } catch (RocketChatCreateGroupException rocketChatCreateGroupException) {
-      assertTrue("Excepted RocketChatCreateGroupException thrown", true);
+      assertTrue(true, "Excepted RocketChatCreateGroupException thrown");
     }
   }
 
   /** Method: deleteGroup */
   @Test
-  public void deleteGroup_Should_ReturnTrue_WhenApiCallIsSuccessful() throws SecurityException {
+  void deleteGroup_Should_ReturnTrue_WhenApiCallIsSuccessful() throws SecurityException {
 
     GroupDeleteResponseDTO response = new GroupDeleteResponseDTO(true);
 
@@ -256,7 +253,7 @@ public void deleteGroup_Should_ReturnTrue_WhenApiCallIsSuccessful() throws Secur
   }
 
   @Test
-  public void deleteGroup_Should_ReturnFalseAndLog_WhenApiCallIsNotSuccessful()
+  void deleteGroup_Should_ReturnFalseAndLog_WhenApiCallIsNotSuccessful()
       throws SecurityException {
 
     GroupDeleteResponseDTO response = new GroupDeleteResponseDTO(false);
@@ -275,7 +272,7 @@ public void deleteGroup_Should_ReturnFalseAndLog_WhenApiCallIsNotSuccessful()
   }
 
   @Test
-  public void rollbackGroup_Should_Log_WhenApiCallFailsWithAnException() throws SecurityException {
+  void rollbackGroup_Should_Log_WhenApiCallFailsWithAnException() throws SecurityException {
 
     HttpServerErrorException httpServerErrorException =
         new HttpServerErrorException(HttpStatus.INTERNAL_SERVER_ERROR, "HttpServerErrorException");
@@ -290,18 +287,18 @@ public void rollbackGroup_Should_Log_WhenApiCallFailsWithAnException() throws Se
 
   /** Method: addUserToGroup */
   @Test
-  public void addUserToGroup_Should_ThrowRocketChatAddUserToGroupException_WheApiCallFails() {
+  void addUserToGroup_Should_ThrowRocketChatAddUserToGroupException_WheApiCallFails() {
 
     try {
       rocketChatService.addUserToGroup(RC_USER_ID, GROUP_ID);
       fail("Expected exception: RocketChatAddUserToGroupException");
     } catch (RocketChatAddUserToGroupException rcAddToGroupEx) {
-      assertTrue("Excepted RocketChatAddUserToGroupException thrown", true);
+      assertTrue(true, "Excepted RocketChatAddUserToGroupException thrown");
     }
   }
 
   @Test
-  public void addUserToGroup_Should_ThrowRocketChatLoginException_WhenResponseIsNotSuccessful()
+  void addUserToGroup_Should_ThrowRocketChatLoginException_WhenResponseIsNotSuccessful()
       throws RocketChatUserNotInitializedException {
 
     GroupResponseDTO groupResponseDTO = new GroupResponseDTO(null, false, "error", "errorType");
@@ -316,13 +313,13 @@ public void addUserToGroup_Should_ThrowRocketChatLoginException_WhenResponseIsNo
       rocketChatService.addUserToGroup(RC_USER_ID, GROUP_ID);
       fail("Expected exception: RocketChatAddUserToGroupException");
     } catch (RocketChatAddUserToGroupException rcAddToGroupEx) {
-      assertTrue("Excepted RocketChatAddUserToGroupException thrown", true);
+      assertTrue(true, "Excepted RocketChatAddUserToGroupException thrown");
     }
   }
 
   /** Method: removeUserFromGroup */
   @Test
-  public void
+  void
       removeUserFromGroup_Should_ThrowRocketChatRemoveUserFromGroupException_WhenAPICallIsNotSuccessful()
           throws RocketChatUserNotInitializedException {
 
@@ -338,12 +335,12 @@ public void addUserToGroup_Should_ThrowRocketChatLoginException_WhenResponseIsNo
       rocketChatService.removeUserFromGroup(RC_USER_ID, GROUP_ID);
       fail("Expected exception: RocketChatRemoveUserFromGroupException");
     } catch (RocketChatRemoveUserFromGroupException ex) {
-      assertTrue("Excepted RocketChatRemoveUserFromGroupException thrown", true);
+      assertTrue(true, "Excepted RocketChatRemoveUserFromGroupException thrown");
     }
   }
 
   @Test
-  public void
+  void
       removeUserFromGroup_Should_ThrowRocketChatRemoveUserFromGroupException_WhenAPIResponseIsUnSuccessful()
           throws Exception {
 
@@ -357,13 +354,13 @@ public void addUserToGroup_Should_ThrowRocketChatLoginException_WhenResponseIsNo
       rocketChatService.removeUserFromGroup(RC_USER_ID, GROUP_ID);
       fail("Expected exception: RocketChatRemoveUserFromGroupException");
     } catch (RocketChatRemoveUserFromGroupException ex) {
-      assertTrue("Excepted RocketChatRemoveUserFromGroupException thrown", true);
+      assertTrue(true, "Excepted RocketChatRemoveUserFromGroupException thrown");
     }
   }
 
   /** Method: createPrivateGroupWithSystemUser */
   @Test
-  public void
+  void
       createPrivateGroupWithSystemUser_Should_ReturnTheGroupId_When_RocketChatApiCallWasSuccessful()
           throws Exception {
 
@@ -382,7 +379,7 @@ public void addUserToGroup_Should_ThrowRocketChatLoginException_WhenResponseIsNo
 
   /** Method: removeSystemMessages */
   @Test
-  public void
+  void
       removeSystemMessages_Should_ThrowRocketChatRemoveSystemMessagesException_WhenApiCallFailsWithAnException()
           throws RocketChatUserNotInitializedException {
 
@@ -401,12 +398,12 @@ public void addUserToGroup_Should_ThrowRocketChatLoginException_WhenResponseIsNo
       rocketChatService.removeSystemMessages(GROUP_ID, DATETIME_OLDEST, DATETIME_LATEST);
       fail("Expected exception: RocketChatRemoveSystemMessagesException");
     } catch (RocketChatRemoveSystemMessagesException rocketChatRemoveSystemMessagesException) {
-      assertTrue("Excepted RocketChatRemoveSystemMessagesException thrown", true);
+      assertTrue(true, "Excepted RocketChatRemoveSystemMessagesException thrown");
     }
   }
 
   @Test
-  public void
+  void
       removeSystemMessages_Should_ThrowRocketChatRemoveSystemMessagesException_WhenDateFormatIsWrong()
           throws RocketChatUserNotInitializedException {
 
@@ -416,29 +413,32 @@ public void addUserToGroup_Should_ThrowRocketChatLoginException_WhenResponseIsNo
       rocketChatService.removeSystemMessages(GROUP_ID, DATETIME_OLDEST, null);
       fail("Expected exception: RocketChatRemoveSystemMessagesException");
     } catch (RocketChatRemoveSystemMessagesException rocketChatRemoveSystemMessagesException) {
-      assertTrue("Excepted RocketChatRemoveSystemMessagesException thrown", true);
+      assertTrue(true, "Excepted RocketChatRemoveSystemMessagesException thrown");
     }
   }
 
-  @Test(expected = RocketChatRemoveSystemMessagesException.class)
-  public void removeSystemMessages_Should_ReturnFalseAndLogError_WhenApiCallIsUnSuccessful()
+  @Test
+  void removeSystemMessages_Should_ReturnFalseAndLogError_WhenApiCallIsUnSuccessful()
       throws Exception {
+    assertThrows(
+        RocketChatRemoveSystemMessagesException.class,
+        () -> {
+          when(restTemplate.postForObject(
+                  ArgumentMatchers.anyString(),
+                  any(),
+                  ArgumentMatchers.<Class<StandardResponseDTO>>any()))
+              .thenReturn(STANDARD_RESPONSE_DTO_ERROR);
 
-    when(restTemplate.postForObject(
-            ArgumentMatchers.anyString(),
-            any(),
-            ArgumentMatchers.<Class<StandardResponseDTO>>any()))
-        .thenReturn(STANDARD_RESPONSE_DTO_ERROR);
-
-    when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
+          when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
 
-    rocketChatService.removeSystemMessages(GROUP_ID, DATETIME_OLDEST, DATETIME_LATEST);
+          rocketChatService.removeSystemMessages(GROUP_ID, DATETIME_OLDEST, DATETIME_LATEST);
 
-    verify(logger, atLeastOnce()).error(anyString(), anyString(), anyString());
+          verify(logger, atLeastOnce()).error(anyString(), anyString(), anyString());
+        });
   }
 
   @Test
-  public void removeSystemMessages_Should_NotThrowException_WhenApiCallIsSuccessful()
+  void removeSystemMessages_Should_NotThrowException_WhenApiCallIsSuccessful()
       throws Exception {
 
     when(restTemplate.postForObject(
@@ -455,7 +455,7 @@ public void removeSystemMessages_Should_NotThrowException_WhenApiCallIsSuccessfu
 
   /** Method: getUserId */
   @Test
-  public void getUserId_Should_LoginUser() throws RocketChatLoginException {
+  void getUserId_Should_LoginUser() throws RocketChatLoginException {
 
     when(rcCredentialsHelper.loginUser(any(), any()))
         .thenReturn(new ResponseEntity<>(LOGIN_RESPONSE_DTO_TECH_USER, HttpStatus.OK));
@@ -472,7 +472,7 @@ public void getUserId_Should_LoginUser() throws RocketChatLoginException {
   }
 
   @Test
-  public void getUserId_Should_LogoutUser() throws RocketChatLoginException {
+  void getUserId_Should_LogoutUser() throws RocketChatLoginException {
 
     when(rcCredentialsHelper.loginUser(any(), any()))
         .thenReturn(new ResponseEntity<>(LOGIN_RESPONSE_DTO_TECH_USER, HttpStatus.OK));
@@ -489,7 +489,7 @@ public void getUserId_Should_LogoutUser() throws RocketChatLoginException {
   }
 
   @Test
-  public void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginException {
+  void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginException {
 
     when(rcCredentialsHelper.loginUser(any(), any()))
         .thenReturn(new ResponseEntity<>(LOGIN_RESPONSE_DTO_TECH_USER, HttpStatus.OK));
@@ -507,7 +507,7 @@ public void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginExcepti
 
   /** Method: getSubscriptionsOfUser */
   @Test
-  public void
+  void
       getSubscriptionsOfUser_Should_ThrowInternalServerErrorException_When_APICallIsNotSuccessful() {
 
     when(restTemplate.exchange(
@@ -521,12 +521,12 @@ public void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginExcepti
       rocketChatService.getSubscriptionsOfUser(RC_CREDENTIALS);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException ex) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
   @Test
-  public void
+  void
       getSubscriptionsOfUser_Should_ThrowInternalServerErrorException_When_APIResponseIsUnSuccessful() {
 
     when(restTemplate.exchange(
@@ -540,12 +540,12 @@ public void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginExcepti
       rocketChatService.getSubscriptionsOfUser(RC_CREDENTIALS);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException ex) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
   @Test
-  public void
+  void
       getSubscriptionsOfUser_Should_ThrowUnauthorizedException_When_RocketChatReturnsUnauthorized() {
 
     when(restTemplate.exchange(
@@ -565,7 +565,7 @@ public void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginExcepti
   }
 
   @Test
-  public void
+  void
       getSubscriptionsOfUser_Should_ReturnListOfSubscriptionsUpdateDTO_When_APICallIsSuccessful() {
 
     when(restTemplate.exchange(
@@ -582,7 +582,7 @@ public void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginExcepti
 
   /** Method: getRoomsOfUser */
   @Test
-  public void
+  void
       getRoomsOfUser_Should_ThrowInternalServerErrorException_When_APICallIsNotSuccessful() {
 
     Exception exception = new RuntimeException(MESSAGE);
@@ -595,12 +595,12 @@ public void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginExcepti
       rocketChatService.getRoomsOfUser(RC_CREDENTIALS);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException ex) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
   @Test
-  public void
+  void
       getRoomsOfUser_Should_ThrowInternalServerErrorException_When_APIResponseIsUnSuccessful() {
 
     when(restTemplate.exchange(
@@ -611,12 +611,12 @@ public void getUserId_Should_ReturnCorrectUserId() throws RocketChatLoginExcepti
       rocketChatService.getRoomsOfUser(RC_CREDENTIALS);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException ex) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
   @Test
-  public void getRoomsOfUser_Should_ReturnListOfRoomsUpdateDTO_WhenAPICallIsSuccessful() {
+  void getRoomsOfUser_Should_ReturnListOfRoomsUpdateDTO_WhenAPICallIsSuccessful() {
 
     when(restTemplate.exchange(
             ArgumentMatchers.anyString(), any(), any(), ArgumentMatchers.<Class<RoomsGetDTO>>any()))
@@ -629,7 +629,7 @@ public void getRoomsOfUser_Should_ReturnListOfRoomsUpdateDTO_WhenAPICallIsSucces
 
   /** Method: removeAllStandardUsersFromGroup */
   @Test
-  public void
+  void
       removeAllStandardUsersFromGroup_Should_ThrowRocketChatGetGroupMembersException_WhenGroupListIsEmpty()
           throws Exception {
 
@@ -641,12 +641,12 @@ public void getRoomsOfUser_Should_ReturnListOfRoomsUpdateDTO_WhenAPICallIsSucces
       spy.removeAllStandardUsersFromGroup(GROUP_ID);
       fail("Expected exception: RocketChatGetGroupMembersException");
     } catch (RocketChatGetGroupMembersException rocketChatGetGroupMembersException) {
-      assertTrue("Excepted RocketChatGetGroupMembersException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetGroupMembersException thrown");
     }
   }
 
   @Test
-  public void
+  void
       removeAllStandardUsersFromGroup_Should_RemoveAllStandardUsersAndNotTechnicalOrSystemUser()
           throws Exception {
 
@@ -669,7 +669,7 @@ public void getRoomsOfUser_Should_ReturnListOfRoomsUpdateDTO_WhenAPICallIsSucces
 
   /** Method: removeAllMessages */
   @Test
-  public void removeAllMessages_Should_NotThrowException_WhenRemoveMessagesSucceeded()
+  void removeAllMessages_Should_NotThrowException_WhenRemoveMessagesSucceeded()
       throws Exception {
 
     when(restTemplate.postForObject(
@@ -683,25 +683,28 @@ public void removeAllMessages_Should_NotThrowException_WhenRemoveMessagesSucceed
     assertDoesNotThrow(() -> rocketChatService.removeAllMessages(GROUP_ID));
   }
 
-  @Test(expected = RocketChatRemoveSystemMessagesException.class)
-  public void
+  @Test
+  void
       removeAllMessages_Should_ThrowRocketChatRemoveSystemMessagesException_WhenRemoveMessagesFails()
           throws Exception {
-
-    when(restTemplate.postForObject(
-            ArgumentMatchers.anyString(),
-            any(),
-            ArgumentMatchers.<Class<StandardResponseDTO>>any()))
-        .thenReturn(STANDARD_RESPONSE_DTO_ERROR);
-
-    when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
-
-    rocketChatService.removeAllMessages(GROUP_ID);
+    assertThrows(
+        RocketChatRemoveSystemMessagesException.class,
+        () -> {
+          when(restTemplate.postForObject(
+                  ArgumentMatchers.anyString(),
+                  any(),
+                  ArgumentMatchers.<Class<StandardResponseDTO>>any()))
+              .thenReturn(STANDARD_RESPONSE_DTO_ERROR);
+
+          when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
+
+          rocketChatService.removeAllMessages(GROUP_ID);
+        });
   }
 
   /** Method: getStandardMembersOfGroup */
   @Test
-  public void
+  void
       getStandardMembersOfGroup_Should_ThrowRocketChatGetGroupMembersException_WhenAPICallIsNotSuccessful() {
 
     Exception exception = new RuntimeException(MESSAGE);
@@ -712,24 +715,24 @@ public void removeAllMessages_Should_NotThrowException_WhenRemoveMessagesSucceed
       rocketChatService.getStandardMembersOfGroup(GROUP_ID);
       fail("Expected exception: RocketChatGetGroupMembersException");
     } catch (RocketChatGetGroupMembersException | RocketChatUserNotInitializedException ex) {
-      assertTrue("Excepted RocketChatGetGroupMembersException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetGroupMembersException thrown");
     }
   }
 
   @Test
-  public void
+  void
       getStandardMembersOfGroup_Should_ThrowRocketChatGetGroupMembersException_WhenAPIResponseIsUnSuccessful()
           throws Exception {
     try {
       rocketChatService.getStandardMembersOfGroup(GROUP_ID);
       fail("Expected exception: RocketChatGetGroupMembersException");
     } catch (RocketChatGetGroupMembersException ex) {
-      assertTrue("Excepted RocketChatGetGroupMembersException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetGroupMembersException thrown");
     }
   }
 
   @Test
-  public void
+  void
       getStandardMembersOfGroup_Should_ReturnListFilteredOfGroupMemberDTO_WhenAPICallIsSuccessful()
           throws Exception {
 
@@ -749,40 +752,50 @@ public void removeAllMessages_Should_NotThrowException_WhenRemoveMessagesSucceed
   }
 
   /** Method: getUserInfo */
-  @Test(expected = InternalServerErrorException.class)
-  public void getUserInfo_Should_ThrowInternalServerExceptionException_WhenAPICallFails()
+  @Test
+  void getUserInfo_Should_ThrowInternalServerExceptionException_WhenAPICallFails()
       throws RocketChatUserNotInitializedException {
-
-    Exception exception =
-        new RestClientResponseException(
-            MESSAGE, HttpStatus.BAD_REQUEST.value(), ERROR, null, null, null);
-
-    when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
-    when(restTemplate.exchange(
-            ArgumentMatchers.anyString(),
-            any(),
-            any(),
-            ArgumentMatchers.<Class<UserInfoResponseDTO>>any(),
-            anyString()))
-        .thenThrow(exception);
-
-    rocketChatService.getUserInfo(RC_USER_ID);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          Exception exception =
+              new RestClientResponseException(
+                  MESSAGE, HttpStatus.BAD_REQUEST.value(), ERROR, null, null, null);
+
+          when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
+          when(restTemplate.exchange(
+                  ArgumentMatchers.anyString(),
+                  any(),
+                  any(),
+                  ArgumentMatchers.<Class<UserInfoResponseDTO>>any(),
+                  anyString()))
+              .thenThrow(exception);
+
+          rocketChatService.getUserInfo(RC_USER_ID);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void getUserInfo_Should_ThrowInternalServerErrorException_WhenAPICallIsNotSuccessful()
+  @Test
+  void getUserInfo_Should_ThrowInternalServerErrorException_WhenAPICallIsNotSuccessful()
       throws RocketChatUserNotInitializedException {
-
-    when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
-    when(restTemplate.exchange(
-            anyString(), eq(HttpMethod.GET), any(), eq(UserInfoResponseDTO.class), anyString()))
-        .thenReturn(new ResponseEntity<>(USER_INFO_RESPONSE_DTO_FAILED, HttpStatus.OK));
-
-    rocketChatService.getUserInfo(RC_USER_ID);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
+          when(restTemplate.exchange(
+                  anyString(),
+                  eq(HttpMethod.GET),
+                  any(),
+                  eq(UserInfoResponseDTO.class),
+                  anyString()))
+              .thenReturn(new ResponseEntity<>(USER_INFO_RESPONSE_DTO_FAILED, HttpStatus.OK));
+
+          rocketChatService.getUserInfo(RC_USER_ID);
+        });
   }
 
   @Test
-  public void getUserInfo_Should_ReturnUserInfoResponseDTOWithSameUserId_WhenAPICallIsSuccessful()
+  void getUserInfo_Should_ReturnUserInfoResponseDTOWithSameUserId_WhenAPICallIsSuccessful()
       throws Exception {
 
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
@@ -800,7 +813,7 @@ public void getUserInfo_Should_ReturnUserInfoResponseDTOWithSameUserId_WhenAPICa
   }
 
   @Test
-  public void updateUser_Should_performRocketChatUpdate()
+  void updateUser_Should_performRocketChatUpdate()
       throws RocketChatUserNotInitializedException {
     UserUpdateRequestDTO userUpdateRequestDTO =
         new EasyRandom().nextObject(UserUpdateRequestDTO.class);
@@ -816,34 +829,48 @@ public void updateUser_Should_performRocketChatUpdate()
             eq(RC_URL_CHAT_USER_UPDATE), eq(HttpMethod.POST), any(), eq(UserInfoResponseDTO.class));
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void updateUser_Should_throwInternalServerErrorException_When_rocketChatUpdateFails()
+  @Test
+  void updateUser_Should_throwInternalServerErrorException_When_rocketChatUpdateFails()
       throws RocketChatUserNotInitializedException {
-    UserUpdateRequestDTO userUpdateRequestDTO =
-        new EasyRandom().nextObject(UserUpdateRequestDTO.class);
-    when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
-    when(restTemplate.exchange(
-            eq(RC_URL_CHAT_USER_UPDATE), eq(HttpMethod.POST), any(), eq(UserInfoResponseDTO.class)))
-        .thenReturn(new ResponseEntity<>(new UserInfoResponseDTO(), HttpStatus.OK));
-
-    this.rocketChatService.updateUser(userUpdateRequestDTO);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          UserUpdateRequestDTO userUpdateRequestDTO =
+              new EasyRandom().nextObject(UserUpdateRequestDTO.class);
+          when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
+          when(restTemplate.exchange(
+                  eq(RC_URL_CHAT_USER_UPDATE),
+                  eq(HttpMethod.POST),
+                  any(),
+                  eq(UserInfoResponseDTO.class)))
+              .thenReturn(new ResponseEntity<>(new UserInfoResponseDTO(), HttpStatus.OK));
+
+          this.rocketChatService.updateUser(userUpdateRequestDTO);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void updateUser_Should_throwInternalServerErrorException_When_rocketChatIsNotReachable()
+  @Test
+  void updateUser_Should_throwInternalServerErrorException_When_rocketChatIsNotReachable()
       throws RocketChatUserNotInitializedException {
-    UserUpdateRequestDTO userUpdateRequestDTO =
-        new EasyRandom().nextObject(UserUpdateRequestDTO.class);
-    when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
-    when(restTemplate.exchange(
-            eq(RC_URL_CHAT_USER_UPDATE), eq(HttpMethod.POST), any(), eq(UserInfoResponseDTO.class)))
-        .thenThrow(mock(RestClientResponseException.class));
-
-    this.rocketChatService.updateUser(userUpdateRequestDTO);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          UserUpdateRequestDTO userUpdateRequestDTO =
+              new EasyRandom().nextObject(UserUpdateRequestDTO.class);
+          when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
+          when(restTemplate.exchange(
+                  eq(RC_URL_CHAT_USER_UPDATE),
+                  eq(HttpMethod.POST),
+                  any(),
+                  eq(UserInfoResponseDTO.class)))
+              .thenThrow(mock(RestClientResponseException.class));
+
+          this.rocketChatService.updateUser(userUpdateRequestDTO);
+        });
   }
 
   @Test
-  public void deleteUser_Should_performRocketDeleteUser() throws Exception {
+  void deleteUser_Should_performRocketDeleteUser() throws Exception {
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
     when(restTemplate.exchange(
             eq(RC_URL_CHAT_USER_DELETE), eq(HttpMethod.POST), any(), eq(UserInfoResponseDTO.class)))
@@ -857,7 +884,7 @@ public void deleteUser_Should_performRocketDeleteUser() throws Exception {
   }
 
   @Test
-  public void deleteUser_Should_performRocketDeleteUserOnAlreadyDeletedResponse() throws Exception {
+  void deleteUser_Should_performRocketDeleteUserOnAlreadyDeletedResponse() throws Exception {
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
     var response =
         new UserInfoResponseDTO(
@@ -876,19 +903,26 @@ public void deleteUser_Should_performRocketDeleteUserOnAlreadyDeletedResponse()
             eq(RC_URL_CHAT_USER_DELETE), eq(HttpMethod.POST), any(), eq(UserInfoResponseDTO.class));
   }
 
-  @Test(expected = RocketChatDeleteUserException.class)
-  public void deleteUser_Should_throwRocketChatDeleteUserException_When_responseIsNotSuccess()
+  @Test
+  void deleteUser_Should_throwRocketChatDeleteUserException_When_responseIsNotSuccess()
       throws Exception {
-    when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
-    when(restTemplate.exchange(
-            eq(RC_URL_CHAT_USER_DELETE), eq(HttpMethod.POST), any(), eq(UserInfoResponseDTO.class)))
-        .thenReturn(new ResponseEntity<>(new UserInfoResponseDTO(), HttpStatus.OK));
-
-    this.rocketChatService.deleteUser("");
+    assertThrows(
+        RocketChatDeleteUserException.class,
+        () -> {
+          when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
+          when(restTemplate.exchange(
+                  eq(RC_URL_CHAT_USER_DELETE),
+                  eq(HttpMethod.POST),
+                  any(),
+                  eq(UserInfoResponseDTO.class)))
+              .thenReturn(new ResponseEntity<>(new UserInfoResponseDTO(), HttpStatus.OK));
+
+          this.rocketChatService.deleteUser("");
+        });
   }
 
   @Test
-  public void deleteGroupAsTechnicalUser_Should_performRocketDeleteUser() throws Exception {
+  void deleteGroupAsTechnicalUser_Should_performRocketDeleteUser() throws Exception {
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
     when(restTemplate.postForObject(eq(RC_URL_GROUPS_DELETE), any(), any()))
         .thenReturn(new ResponseEntity<>(new GroupDeleteResponseDTO(true), HttpStatus.OK));
@@ -898,17 +932,21 @@ public void deleteGroupAsTechnicalUser_Should_performRocketDeleteUser() throws E
     verify(this.restTemplate, times(1)).postForObject(eq(RC_URL_GROUPS_DELETE), any(), any());
   }
 
-  @Test(expected = RocketChatDeleteGroupException.class)
-  public void
+  @Test
+  void
       deleteGroupAsTechnicalUser_Should_throwRocketChatDeleteUserException_When_responseIsNotSuccess()
           throws Exception {
-    when(rcCredentialsHelper.getTechnicalUser()).thenThrow(new RuntimeException());
+    assertThrows(
+        RocketChatDeleteGroupException.class,
+        () -> {
+          when(rcCredentialsHelper.getTechnicalUser()).thenThrow(new RuntimeException());
 
-    this.rocketChatService.deleteGroupAsTechnicalUser("");
+          this.rocketChatService.deleteGroupAsTechnicalUser("");
+        });
   }
 
   @Test
-  public void deleteGroupAsSystemUser_Should_performRocketDeleteUser() throws Exception {
+  void deleteGroupAsSystemUser_Should_performRocketDeleteUser() throws Exception {
     when(rcCredentialsHelper.getSystemUser()).thenReturn(RC_CREDENTIALS_SYSTEM_A);
     when(restTemplate.postForObject(eq(RC_URL_GROUPS_DELETE), any(), any()))
         .thenReturn(new ResponseEntity<>(new GroupDeleteResponseDTO(true), HttpStatus.OK));
@@ -918,19 +956,23 @@ public void deleteGroupAsSystemUser_Should_performRocketDeleteUser() throws Exce
     verify(this.restTemplate, times(1)).postForObject(eq(RC_URL_GROUPS_DELETE), any(), any());
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       deleteGroupAsSystemUser_Should_throwInternalServerErrorException_When_responseIsNotSuccess()
           throws Exception {
-    when(rcCredentialsHelper.getSystemUser())
-        .thenThrow(new RocketChatUserNotInitializedException(""));
-
-    this.rocketChatService.deleteGroupAsSystemUser("");
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(rcCredentialsHelper.getSystemUser())
+              .thenThrow(new RocketChatUserNotInitializedException(""));
+
+          this.rocketChatService.deleteGroupAsSystemUser("");
+        });
   }
 
   @Test
   @SuppressWarnings("unchecked")
-  public void setRoomReadOnly_Should_performRocketChatSetRoomReadOnly() throws Exception {
+  void setRoomReadOnly_Should_performRocketChatSetRoomReadOnly() throws Exception {
     when(rcCredentialsHelper.getSystemUser()).thenReturn(RC_CREDENTIALS_SYSTEM_A);
     when(restTemplate.exchange(
             eq(RC_URL_GROUPS_SET_READ_ONLY),
@@ -956,7 +998,7 @@ public void setRoomReadOnly_Should_performRocketChatSetRoomReadOnly() throws Exc
   }
 
   @Test
-  public void setRoomReadOnly_Should_logError_When_responseIsNotSuccess() throws Exception {
+  void setRoomReadOnly_Should_logError_When_responseIsNotSuccess() throws Exception {
     when(rcCredentialsHelper.getSystemUser()).thenReturn(RC_CREDENTIALS_SYSTEM_A);
     GroupResponseDTO groupResponseDTO = new GroupResponseDTO();
     groupResponseDTO.setSuccess(false);
@@ -974,7 +1016,7 @@ public void setRoomReadOnly_Should_logError_When_responseIsNotSuccess() throws E
 
   @Test
   @SuppressWarnings("unchecked")
-  public void setRoomWriteable_Should_performRocketChatSetRoomReadOnly() throws Exception {
+  void setRoomWriteable_Should_performRocketChatSetRoomReadOnly() throws Exception {
     when(rcCredentialsHelper.getSystemUser()).thenReturn(RC_CREDENTIALS_SYSTEM_A);
     when(restTemplate.exchange(
             eq(RC_URL_GROUPS_SET_READ_ONLY),
@@ -1000,7 +1042,7 @@ public void setRoomWriteable_Should_performRocketChatSetRoomReadOnly() throws Ex
   }
 
   @Test
-  public void setRoomWriteable_Should_logError_When_responseIsNotSuccess() throws Exception {
+  void setRoomWriteable_Should_logError_When_responseIsNotSuccess() throws Exception {
     when(rcCredentialsHelper.getSystemUser()).thenReturn(RC_CREDENTIALS_SYSTEM_A);
     GroupResponseDTO groupResponseDTO = new GroupResponseDTO();
     groupResponseDTO.setSuccess(false);
@@ -1017,7 +1059,7 @@ public void setRoomWriteable_Should_logError_When_responseIsNotSuccess() throws
   }
 
   @Test
-  public void
+  void
       fetchAllInactivePrivateGroupsSinceGivenDate_ShouldThrowException_WhenRocketChatCallFails()
           throws RocketChatUserNotInitializedException {
 
@@ -1036,13 +1078,13 @@ public void setRoomWriteable_Should_logError_When_responseIsNotSuccess() throws
       this.rocketChatService.fetchAllInactivePrivateGroupsSinceGivenDate(LocalDateTime.now());
       fail("Expected exception: RocketChatGetGroupsListAllException");
     } catch (RocketChatGetGroupsListAllException ex) {
-      assertTrue("Excepted RocketChatGetGroupsListAllException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetGroupsListAllException thrown");
       assertEquals("Could not get all rocket chat groups", ex.getMessage());
     }
   }
 
   @Test
-  public void
+  void
       fetchAllInactivePrivateGroupsSinceGivenDate_Should_ThrowException_WhenHttpStatusFromRocketChatCallIsNotOk()
           throws RocketChatUserNotInitializedException {
 
@@ -1060,13 +1102,13 @@ public void setRoomWriteable_Should_logError_When_responseIsNotSuccess() throws
       this.rocketChatService.fetchAllInactivePrivateGroupsSinceGivenDate(LocalDateTime.now());
       fail("Expected exception: RocketChatGetGroupsListAllException");
     } catch (RocketChatGetGroupsListAllException ex) {
-      assertTrue("Excepted RocketChatGetGroupsListAllException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetGroupsListAllException thrown");
       assertEquals("Could not get all rocket chat groups", ex.getMessage());
     }
   }
 
   @Test
-  public void fetchAllInactivePrivateGroupsSinceGivenDate_Should_ReturnCorrectGroupDtoList()
+  void fetchAllInactivePrivateGroupsSinceGivenDate_Should_ReturnCorrectGroupDtoList()
       throws RocketChatUserNotInitializedException, RocketChatGetGroupsListAllException {
 
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
@@ -1087,7 +1129,7 @@ public void fetchAllInactivePrivateGroupsSinceGivenDate_Should_ReturnCorrectGrou
   }
 
   @Test
-  public void fetchAllInactivePrivateGroupsSinceGivenDate_Should_UseCorrectMongoQuery()
+  void fetchAllInactivePrivateGroupsSinceGivenDate_Should_UseCorrectMongoQuery()
       throws RocketChatUserNotInitializedException, RocketChatGetGroupsListAllException {
 
     LocalDateTime dateToCheck = LocalDateTime.of(2021, 1, 1, 0, 0, 0);
@@ -1116,7 +1158,7 @@ public void fetchAllInactivePrivateGroupsSinceGivenDate_Should_UseCorrectMongoQu
   }
 
   @Test
-  public void
+  void
       fetchAllInactivePrivateGroupsSinceGivenDate_Should_CallRocketChatApiMultipleTimes_When_ResultIsPaginated()
           throws RocketChatUserNotInitializedException, RocketChatGetGroupsListAllException {
 
@@ -1146,7 +1188,7 @@ public void fetchAllInactivePrivateGroupsSinceGivenDate_Should_UseCorrectMongoQu
   }
 
   @Test
-  public void
+  void
       fetchAllInactivePrivateGroupsSinceGivenDate_Should_CallRocketChatApiOnlyOnce_When_ResponseContainsTotalOfZeroElements()
           throws RocketChatUserNotInitializedException, RocketChatGetGroupsListAllException {
 
@@ -1178,7 +1220,7 @@ public void fetchAllInactivePrivateGroupsSinceGivenDate_Should_UseCorrectMongoQu
   }
 
   @Test
-  public void getRocketChatUserIdByUsername_Should_ThrowException_WhenRocketChatCallFails()
+  void getRocketChatUserIdByUsername_Should_ThrowException_WhenRocketChatCallFails()
       throws RocketChatUserNotInitializedException {
 
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
@@ -1197,13 +1239,13 @@ public void getRocketChatUserIdByUsername_Should_ThrowException_WhenRocketChatCa
       this.rocketChatService.getRocketChatUserIdByUsername(USERNAME);
       fail("Expected exception: RocketChatGetUserIdException");
     } catch (RocketChatGetUserIdException ex) {
-      assertTrue("Excepted RocketChatGetUserIdException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetUserIdException thrown");
       assertEquals("Could not get users list from Rocket.Chat", ex.getMessage());
     }
   }
 
   @Test
-  public void getRocketChatUserIdByUsername_Should_ThrowException_WhenFoundNoUserByUsername()
+  void getRocketChatUserIdByUsername_Should_ThrowException_WhenFoundNoUserByUsername()
       throws RocketChatUserNotInitializedException {
 
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
@@ -1220,13 +1262,13 @@ public void getRocketChatUserIdByUsername_Should_ThrowException_WhenFoundNoUserB
       this.rocketChatService.getRocketChatUserIdByUsername(USERNAME);
       fail("Expected exception: RocketChatGetUserIdException");
     } catch (RocketChatGetUserIdException ex) {
-      assertTrue("Excepted RocketChatGetUserIdException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetUserIdException thrown");
       assertEquals("Found 0 users by username", ex.getMessage());
     }
   }
 
   @Test
-  public void getRocketChatUserIdByUsername_Should_ThrowException_WhenFound2UsersByUsername()
+  void getRocketChatUserIdByUsername_Should_ThrowException_WhenFound2UsersByUsername()
       throws RocketChatUserNotInitializedException {
 
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
@@ -1243,13 +1285,13 @@ public void getRocketChatUserIdByUsername_Should_ThrowException_WhenFound2UsersB
       this.rocketChatService.getRocketChatUserIdByUsername(USERNAME);
       fail("Expected exception: RocketChatGetUserIdException");
     } catch (RocketChatGetUserIdException ex) {
-      assertTrue("Excepted RocketChatGetUserIdException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetUserIdException thrown");
       assertEquals("Found 2 users by username", ex.getMessage());
     }
   }
 
   @Test
-  public void
+  void
       getRocketChatUserIdByUsername_Should_ThrowException_WhenHttpStatusFromRocketChatCallIsNotOk()
           throws RocketChatUserNotInitializedException {
 
@@ -1267,13 +1309,13 @@ public void getRocketChatUserIdByUsername_Should_ThrowException_WhenFound2UsersB
       this.rocketChatService.getRocketChatUserIdByUsername(USERNAME);
       fail("Expected exception: RocketChatGetUserIdException");
     } catch (RocketChatGetUserIdException ex) {
-      assertTrue("Excepted RocketChatGetUserIdException thrown", true);
+      assertTrue(true, "Excepted RocketChatGetUserIdException thrown");
       assertEquals("Could not get users list from Rocket.Chat", ex.getMessage());
     }
   }
 
   @Test
-  public void getRocketChatUserIdByUsername_Should_ReturnRocketChatUserId()
+  void getRocketChatUserIdByUsername_Should_ReturnRocketChatUserId()
       throws RocketChatUserNotInitializedException, RocketChatGetUserIdException {
 
     when(rcCredentialsHelper.getTechnicalUser()).thenReturn(RC_CREDENTIALS_TECHNICAL_A);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/SessionDataServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/SessionDataServiceTest.java
index 315765601..d8d8b2ae2 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/SessionDataServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/SessionDataServiceTest.java
@@ -1,6 +1,7 @@
 package de.caritas.cob.userservice.api.service;
 
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.SESSION_ID;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -14,13 +15,13 @@
 import de.caritas.cob.userservice.api.service.session.SessionService;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class SessionDataServiceTest {
 
   @InjectMocks private SessionDataService sessionDataService;
@@ -30,12 +31,16 @@ public class SessionDataServiceTest {
 
   private final EasyRandom easyRandom = new EasyRandom();
 
-  @Test(expected = NotFoundException.class)
+  @Test
   public void saveSessionDataForSessionId_Should_ThrowNotFoundException_When_SessionNotFound() {
-    SessionDataDTO sessionData = easyRandom.nextObject(SessionDataDTO.class);
-    when(sessionService.getSession(any())).thenReturn(Optional.empty());
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          SessionDataDTO sessionData = easyRandom.nextObject(SessionDataDTO.class);
+          when(sessionService.getSession(any())).thenReturn(Optional.empty());
 
-    sessionDataService.saveSessionData(SESSION_ID, sessionData);
+          sessionDataService.saveSessionData(SESSION_ID, sessionData);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/UserAgencyServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/UserAgencyServiceTest.java
index 2f5a2db22..d398a1591 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/UserAgencyServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/UserAgencyServiceTest.java
@@ -7,10 +7,7 @@
 import static org.hamcrest.CoreMatchers.everyItem;
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -20,15 +17,15 @@
 import de.caritas.cob.userservice.api.model.UserAgency;
 import de.caritas.cob.userservice.api.port.out.UserAgencyRepository;
 import java.util.List;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.springframework.dao.DataAccessException;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class UserAgencyServiceTest {
 
   @InjectMocks private UserAgencyService userAgencyService;
@@ -47,7 +44,7 @@ public void saveUserAgency_Should_ThrowInternalServerErrorException_When_Databas
       userAgencyService.saveUserAgency(USER_AGENCY);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException serviceException) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
@@ -75,7 +72,7 @@ public void getUserAgenciesByUser_Should_ReturnInternalServerErrorException_When
       userAgencyService.getUserAgenciesByUser(USER);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException serviceEx) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
@@ -102,7 +99,7 @@ public void deleteUserAgency_Should_ThrowInternalServerErrorException_When_Datab
       userAgencyService.deleteUserAgency(USER_AGENCY);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException serviceEx) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
@@ -116,7 +113,7 @@ public void deleteUserAgency_Should_ThrowIllegalArgumentException_When_UserAgenc
       userAgencyService.deleteUserAgency(null);
       fail("Expected exception: InternalServerErrorException");
     } catch (InternalServerErrorException serviceEx) {
-      assertTrue("Excepted InternalServerErrorException thrown", true);
+      assertTrue(true, "Excepted InternalServerErrorException thrown");
     }
   }
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/archive/SessionArchiveServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/archive/SessionArchiveServiceTest.java
index a3bd88221..e4d39709e 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/archive/SessionArchiveServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/archive/SessionArchiveServiceTest.java
@@ -2,6 +2,7 @@
 
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.SESSION_ID;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.doThrow;
 import static org.mockito.Mockito.times;
@@ -25,17 +26,17 @@
 import de.caritas.cob.userservice.api.service.statistics.event.StatisticsEvent;
 import de.caritas.cob.userservice.statisticsservice.generated.web.model.EventType;
 import java.util.Optional;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class SessionArchiveServiceTest {
 
   @InjectMocks SessionArchiveService sessionArchiveService;
@@ -63,44 +64,53 @@ public class SessionArchiveServiceTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setUp() {
     setInternalState(SessionArchiveService.class, "log", logger);
   }
 
-  @Test(expected = NotFoundException.class)
+  @Test
   public void archiveSession_Should_ThrowNotFoundException_WhenSessionIsNotFound() {
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.empty());
 
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.empty());
-
-    sessionArchiveService.archiveSession(SESSION_ID);
+          sessionArchiveService.archiveSession(SESSION_ID);
+        });
   }
 
-  @Test(expected = ConflictException.class)
+  @Test
   public void
       archiveSession_Should_ThrowConflictException_WhenSessionShouldBeArchivedAndIsNotInProgress() {
-
-    Session session = Mockito.mock(Session.class);
-    when(session.isAdvised(any())).thenReturn(true);
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
-    doThrow(new ConflictException("Conflict"))
-        .when(sessionArchiveValidator)
-        .isValidForArchiving(session);
-
-    sessionArchiveService.archiveSession(SESSION_ID);
-    verify(session, times(0)).setStatus(SessionStatus.IN_ARCHIVE);
+    assertThrows(
+        ConflictException.class,
+        () -> {
+          Session session = Mockito.mock(Session.class);
+          when(session.isAdvised(any())).thenReturn(true);
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
+          doThrow(new ConflictException("Conflict"))
+              .when(sessionArchiveValidator)
+              .isValidForArchiving(session);
+
+          sessionArchiveService.archiveSession(SESSION_ID);
+          verify(session, times(0)).setStatus(SessionStatus.IN_ARCHIVE);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void
       archiveSession_Should_ThrowForbiddenException_WhenConsultantHasaNoAuthorizationForTheSession() {
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Session session = Mockito.mock(Session.class);
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
 
-    Session session = Mockito.mock(Session.class);
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
-
-    sessionArchiveService.archiveSession(SESSION_ID);
+          sessionArchiveService.archiveSession(SESSION_ID);
 
-    verify(session, times(0)).setStatus(SessionStatus.IN_ARCHIVE);
+          verify(session, times(0)).setStatus(SessionStatus.IN_ARCHIVE);
+        });
   }
 
   @Test
@@ -115,16 +125,19 @@ public void archiveSession_Should_ChangeStatusOfSession_WhenConsultantHasPermiss
     verify(session, times(1)).setStatus(SessionStatus.IN_ARCHIVE);
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void
       archiveSession_Should_ThrowForbiddenException_WhenUserHasNoAuthorizationForTheSession() {
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Session session = Mockito.mock(Session.class);
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
 
-    Session session = Mockito.mock(Session.class);
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
-
-    sessionArchiveService.archiveSession(SESSION_ID);
+          sessionArchiveService.archiveSession(SESSION_ID);
 
-    verify(session, times(0)).setStatus(SessionStatus.IN_ARCHIVE);
+          verify(session, times(0)).setStatus(SessionStatus.IN_ARCHIVE);
+        });
   }
 
   @Test
@@ -171,61 +184,77 @@ public void archiveSession_Should_LogButNotFail_WhenErrorDuringStatisticsArchive
         .error("Could not create session archive statistics event", illegalStateException);
   }
 
-  @Test(expected = NotFoundException.class)
+  @Test
   public void dearchiveSession_Should_ThrowNotFoundException_WhenSessionIsNotFound() {
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.empty());
-    sessionArchiveService.dearchiveSession(SESSION_ID);
+    assertThrows(
+        NotFoundException.class,
+        () -> {
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.empty());
+          sessionArchiveService.dearchiveSession(SESSION_ID);
+        });
   }
 
-  @Test(expected = ConflictException.class)
+  @Test
   public void
       dearchiveSession_Should_ThrowConflictException_WhenSessionShouldBeReactivatedAndIsAlreadyInProgress() {
-
-    Session session = Mockito.mock(Session.class);
-    when(session.isAdvised(any())).thenReturn(true);
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
-    doThrow(new ConflictException("Conflict"))
-        .when(sessionArchiveValidator)
-        .isValidForDearchiving(session);
-
-    sessionArchiveService.dearchiveSession(SESSION_ID);
-
-    verify(session, times(0)).setStatus(SessionStatus.IN_PROGRESS);
+    assertThrows(
+        ConflictException.class,
+        () -> {
+          Session session = Mockito.mock(Session.class);
+          when(session.isAdvised(any())).thenReturn(true);
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
+          doThrow(new ConflictException("Conflict"))
+              .when(sessionArchiveValidator)
+              .isValidForDearchiving(session);
+
+          sessionArchiveService.dearchiveSession(SESSION_ID);
+
+          verify(session, times(0)).setStatus(SessionStatus.IN_PROGRESS);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void
       dearchiveSession_Should_ThrowForbiddenException_WhenConsultantHasNoAuthorizationForTheSession() {
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Session session = Mockito.mock(Session.class);
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
 
-    Session session = Mockito.mock(Session.class);
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
+          sessionArchiveService.dearchiveSession(SESSION_ID);
 
-    sessionArchiveService.dearchiveSession(SESSION_ID);
-
-    verify(session, times(0)).setStatus(SessionStatus.IN_PROGRESS);
+          verify(session, times(0)).setStatus(SessionStatus.IN_PROGRESS);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void
       dearchiveSession_Should_ThrowForbiddenException_WhenSessionIsNotTeamSessionAndConsultantNotAssigned() {
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Session session = Mockito.mock(Session.class);
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
 
-    Session session = Mockito.mock(Session.class);
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
-
-    sessionArchiveService.dearchiveSession(SESSION_ID);
+          sessionArchiveService.dearchiveSession(SESSION_ID);
 
-    verify(session, times(1)).setStatus(SessionStatus.IN_ARCHIVE);
+          verify(session, times(1)).setStatus(SessionStatus.IN_ARCHIVE);
+        });
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void dearchiveSession_Should_ThrowForbiddenException_WhenNoConsultantOrUserRole() {
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Session session = Mockito.mock(Session.class);
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
 
-    Session session = Mockito.mock(Session.class);
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
-
-    sessionArchiveService.dearchiveSession(SESSION_ID);
+          sessionArchiveService.dearchiveSession(SESSION_ID);
 
-    verify(session, times(0)).setStatus(SessionStatus.IN_PROGRESS);
+          verify(session, times(0)).setStatus(SessionStatus.IN_PROGRESS);
+        });
   }
 
   @Test
@@ -239,16 +268,19 @@ public void dearchiveSession_Should_ChangeStatusOfSession_WhenConsultantHasPermi
     verify(session, times(1)).setStatus(SessionStatus.IN_PROGRESS);
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void
       dearchiveSession_Should_ThrowForbiddenException_WhenUserHasNoAuthorizationForTheSession() {
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Session session = Mockito.mock(Session.class);
+          when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
 
-    Session session = Mockito.mock(Session.class);
-    when(sessionRepository.findById(SESSION_ID)).thenReturn(Optional.of(session));
-
-    sessionArchiveService.dearchiveSession(SESSION_ID);
+          sessionArchiveService.dearchiveSession(SESSION_ID);
 
-    verify(session, times(1)).setStatus(SessionStatus.IN_ARCHIVE);
+          verify(session, times(1)).setStatus(SessionStatus.IN_ARCHIVE);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/conversation/anonymous/AnonymousConversationCreatorServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/conversation/anonymous/AnonymousConversationCreatorServiceTest.java
index 41978291b..da37ee373 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/conversation/anonymous/AnonymousConversationCreatorServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/conversation/anonymous/AnonymousConversationCreatorServiceTest.java
@@ -6,6 +6,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_DTO_SUCHT;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyBoolean;
 import static org.mockito.ArgumentMatchers.anyString;
@@ -32,14 +33,14 @@
 import de.caritas.cob.userservice.api.service.user.UserService;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
-public class AnonymousConversationCreatorServiceTest {
+@ExtendWith(SpringExtension.class)
+class AnonymousConversationCreatorServiceTest {
 
   @InjectMocks private AnonymousConversationCreatorService anonymousConversationCreatorService;
   @Mock private UserService userService;
@@ -52,70 +53,88 @@ public class AnonymousConversationCreatorServiceTest {
 
   EasyRandom easyRandom = new EasyRandom();
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createAnonymousConversation_Should_ThrowInternalServerErrorException_When_ProvidedUserDoesNotExist() {
-    when(userService.getUser(anyString())).thenReturn(Optional.empty());
-    AnonymousUserCredentials credentials = easyRandom.nextObject(AnonymousUserCredentials.class);
-
-    anonymousConversationCreatorService.createAnonymousConversation(USER_DTO_SUCHT, credentials);
-
-    verifyNoInteractions(sessionService);
-    verifyNoInteractions(rollbackFacade);
-    verifyNoInteractions(createEnquiryMessageFacade);
-    verifyNoInteractions(agencyService);
-    verifyNoInteractions(consultantAgencyService);
-    verifyNoInteractions(liveEventNotificationService);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(userService.getUser(anyString())).thenReturn(Optional.empty());
+          AnonymousUserCredentials credentials =
+              easyRandom.nextObject(AnonymousUserCredentials.class);
+
+          anonymousConversationCreatorService.createAnonymousConversation(
+              USER_DTO_SUCHT, credentials);
+
+          verifyNoInteractions(sessionService);
+          verifyNoInteractions(rollbackFacade);
+          verifyNoInteractions(createEnquiryMessageFacade);
+          verifyNoInteractions(agencyService);
+          verifyNoInteractions(consultantAgencyService);
+          verifyNoInteractions(liveEventNotificationService);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createAnonymousConversation_Should_ThrowInternalServerErrorExceptionAndPerformRollback_When_InitializingSessionFails() {
-    when(userService.getUser(anyString())).thenReturn(Optional.of(USER));
-    when(sessionService.initializeSession(
-            any(User.class),
-            any(UserDTO.class),
-            anyBoolean(),
-            any(RegistrationType.class),
-            any(SessionStatus.class)))
-        .thenThrow(new IllegalArgumentException());
-    AnonymousUserCredentials credentials = easyRandom.nextObject(AnonymousUserCredentials.class);
-
-    anonymousConversationCreatorService.createAnonymousConversation(USER_DTO_SUCHT, credentials);
-
-    verifyNoInteractions(rollbackFacade);
-    verifyNoInteractions(createEnquiryMessageFacade);
-    verifyNoInteractions(agencyService);
-    verifyNoInteractions(consultantAgencyService);
-    verifyNoInteractions(liveEventNotificationService);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(userService.getUser(anyString())).thenReturn(Optional.of(USER));
+          when(sessionService.initializeSession(
+                  any(User.class),
+                  any(UserDTO.class),
+                  anyBoolean(),
+                  any(RegistrationType.class),
+                  any(SessionStatus.class)))
+              .thenThrow(new IllegalArgumentException());
+          AnonymousUserCredentials credentials =
+              easyRandom.nextObject(AnonymousUserCredentials.class);
+
+          anonymousConversationCreatorService.createAnonymousConversation(
+              USER_DTO_SUCHT, credentials);
+
+          verifyNoInteractions(rollbackFacade);
+          verifyNoInteractions(createEnquiryMessageFacade);
+          verifyNoInteractions(agencyService);
+          verifyNoInteractions(consultantAgencyService);
+          verifyNoInteractions(liveEventNotificationService);
+        });
   }
 
-  @Test(expected = InternalServerErrorException.class)
-  public void
+  @Test
+  void
       createAnonymousConversation_Should_ThrowInternalServerErrorExceptionAndPerformRollback_When_CreateRcRoomFails()
           throws CreateEnquiryException {
-    when(userService.getUser(anyString())).thenReturn(Optional.of(USER));
-    when(sessionService.initializeSession(
-            any(User.class),
-            any(UserDTO.class),
-            anyBoolean(),
-            any(RegistrationType.class),
-            any(SessionStatus.class)))
-        .thenReturn(SESSION);
-    CreateEnquiryException exception = easyRandom.nextObject(CreateEnquiryException.class);
-    when(createEnquiryMessageFacade.createRocketChatRoomAndAddUsers(any(), any(), any()))
-        .thenThrow(exception);
-    AnonymousUserCredentials credentials = easyRandom.nextObject(AnonymousUserCredentials.class);
-
-    anonymousConversationCreatorService.createAnonymousConversation(USER_DTO_SUCHT, credentials);
-
-    verifyNoInteractions(agencyService);
-    verifyNoInteractions(consultantAgencyService);
-    verifyNoInteractions(liveEventNotificationService);
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(userService.getUser(anyString())).thenReturn(Optional.of(USER));
+          when(sessionService.initializeSession(
+                  any(User.class),
+                  any(UserDTO.class),
+                  anyBoolean(),
+                  any(RegistrationType.class),
+                  any(SessionStatus.class)))
+              .thenReturn(SESSION);
+          CreateEnquiryException exception = easyRandom.nextObject(CreateEnquiryException.class);
+          when(createEnquiryMessageFacade.createRocketChatRoomAndAddUsers(any(), any(), any()))
+              .thenThrow(exception);
+          AnonymousUserCredentials credentials =
+              easyRandom.nextObject(AnonymousUserCredentials.class);
+
+          anonymousConversationCreatorService.createAnonymousConversation(
+              USER_DTO_SUCHT, credentials);
+
+          verifyNoInteractions(agencyService);
+          verifyNoInteractions(consultantAgencyService);
+          verifyNoInteractions(liveEventNotificationService);
+        });
   }
 
   @Test
-  public void createAnonymousConversation_Should_ReturnSessionAndTriggerLiveEvent()
+  void createAnonymousConversation_Should_ReturnSessionAndTriggerLiveEvent()
       throws CreateEnquiryException {
     when(userService.getUser(anyString())).thenReturn(Optional.of(USER));
     when(sessionService.initializeSession(
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/AssignEnquiryEmailSupplierTest.java b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/AssignEnquiryEmailSupplierTest.java
index 4e59ccbc0..230ca8b56 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/AssignEnquiryEmailSupplierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/AssignEnquiryEmailSupplierTest.java
@@ -18,14 +18,14 @@
 import de.caritas.cob.userservice.mailservice.generated.web.model.TemplateDataDTO;
 import java.util.List;
 import java.util.Optional;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class AssignEnquiryEmailSupplierTest {
 
   private AssignEnquiryEmailSupplier assignEnquiryEmailSupplier;
@@ -36,7 +36,7 @@ public class AssignEnquiryEmailSupplierTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     String applicationBaseUrl = "application base url";
     String askerUserName = "asker user name";
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewDirectEnquiryEmailSupplierTest.java b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewDirectEnquiryEmailSupplierTest.java
index 4ea28d9ba..c456023a4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewDirectEnquiryEmailSupplierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewDirectEnquiryEmailSupplierTest.java
@@ -24,13 +24,13 @@
 import de.caritas.cob.userservice.mailservice.generated.web.model.MailDTO;
 import java.util.List;
 import org.assertj.core.api.Assertions;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class NewDirectEnquiryEmailSupplierTest {
 
   private NewDirectEnquiryEmailSupplier newDirectEnquiryEmailSupplier;
@@ -38,7 +38,7 @@ public class NewDirectEnquiryEmailSupplierTest {
   @Mock private ConsultantAgencyRepository consultantAgencyRepository;
   @Mock private ReleaseToggleService releaseToggleService;
 
-  @Before
+  @BeforeEach
   public void setup() {
     newDirectEnquiryEmailSupplier =
         new NewDirectEnquiryEmailSupplier(consultantAgencyRepository, null, releaseToggleService);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewEnquiryEmailSupplierTest.java b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewEnquiryEmailSupplierTest.java
index ca21f4692..408978d55 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewEnquiryEmailSupplierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewEnquiryEmailSupplierTest.java
@@ -22,13 +22,13 @@
 import de.caritas.cob.userservice.mailservice.generated.web.model.MailDTO;
 import de.caritas.cob.userservice.mailservice.generated.web.model.TemplateDataDTO;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class NewEnquiryEmailSupplierTest {
 
   private NewEnquiryEmailSupplier newEnquiryEmailSupplier;
@@ -41,7 +41,7 @@ public class NewEnquiryEmailSupplierTest {
 
   @Mock private ReleaseToggleService releaseToggleService;
 
-  @Before
+  @BeforeEach
   public void setup() {
     this.newEnquiryEmailSupplier =
         new NewEnquiryEmailSupplier(
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewFeedbackEmailSupplierTest.java b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewFeedbackEmailSupplierTest.java
index f2f67703e..08b6c25b4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewFeedbackEmailSupplierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewFeedbackEmailSupplierTest.java
@@ -31,14 +31,14 @@
 import java.util.Optional;
 import java.util.UUID;
 import org.apache.commons.lang3.RandomStringUtils;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class NewFeedbackEmailSupplierTest {
 
   private static final ObjectMapper MAPPER = new ObjectMapper();
@@ -55,7 +55,7 @@ public class NewFeedbackEmailSupplierTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     this.newFeedbackEmailSupplier =
         new NewFeedbackEmailSupplier(
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewMessageEmailSupplierTest.java b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewMessageEmailSupplierTest.java
index 23db51ef4..fe4ee49bd 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewMessageEmailSupplierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/emailsupplier/NewMessageEmailSupplierTest.java
@@ -12,6 +12,7 @@
 import static org.hamcrest.Matchers.empty;
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.is;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.anyString;
@@ -45,16 +46,19 @@
 import java.util.Optional;
 import java.util.Set;
 import org.apache.commons.lang3.StringUtils;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 import org.slf4j.Logger;
 import org.springframework.test.util.ReflectionTestUtils;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
 public class NewMessageEmailSupplierTest {
 
   private NewMessageEmailSupplier newMessageEmailSupplier;
@@ -77,7 +81,7 @@ public class NewMessageEmailSupplierTest {
 
   @Mock private ReleaseToggleService releaseToggleService;
 
-  @Before
+  @BeforeEach
   public void setup() {
     this.newMessageEmailSupplier =
         NewMessageEmailSupplier.builder()
@@ -367,16 +371,20 @@ public void generateEmails_Should_ReturnExpectedEmailToAdviceSeeker_When_AdviceS
     TenantContext.clear();
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void generateEmails_Should_ThrowInternalServerException_When_ConsultantIsNotFound() {
-    when(roles.contains(UserRole.CONSULTANT.getValue())).thenReturn(true);
-    Consultant consultant = mock(Consultant.class);
-    when(session.getConsultant()).thenReturn(consultant);
-    when(consultant.getId()).thenReturn(CONSULTANT_ID);
-    when(session.getUser()).thenReturn(USER);
-    when(consultantService.getConsultant(USER.getUserId())).thenReturn(Optional.empty());
-
-    this.newMessageEmailSupplier.generateEmails();
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(roles.contains(UserRole.CONSULTANT.getValue())).thenReturn(true);
+          Consultant consultant = mock(Consultant.class);
+          when(session.getConsultant()).thenReturn(consultant);
+          when(consultant.getId()).thenReturn(CONSULTANT_ID);
+          when(session.getUser()).thenReturn(USER);
+          when(consultantService.getConsultant(USER.getUserId())).thenReturn(Optional.empty());
+
+          this.newMessageEmailSupplier.generateEmails();
+        });
   }
 
   private void givenCurrentTenantDataIsSet() {
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/helper/AgencySecurityHeaderSupplierTest.java b/src/test/java/de/caritas/cob/userservice/api/service/helper/AgencySecurityHeaderSupplierTest.java
index 9f1c97e7b..14e63504b 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/helper/AgencySecurityHeaderSupplierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/helper/AgencySecurityHeaderSupplierTest.java
@@ -5,7 +5,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.AGENCY_ID_LIST;
 import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
@@ -21,19 +21,22 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import lombok.SneakyThrows;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentMatchers;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 import org.springframework.cache.annotation.Cacheable;
 import org.springframework.http.HttpHeaders;
 import org.springframework.web.context.request.RequestContextHolder;
 
-@RunWith(MockitoJUnitRunner.class)
-public class AgencySecurityHeaderSupplierTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class AgencySecurityHeaderSupplierTest {
 
   private final String GET_AGENCY_METHOD_NAME = "getAgency";
   private final String GET_AGENCIES_METHOD_NAME = "getAgencies";
@@ -52,8 +55,8 @@ public class AgencySecurityHeaderSupplierTest {
 
   @Mock private AgencyServiceApiControllerFactory agencyServiceApiControllerFactory;
 
-  @Before
-  public void setup() throws NoSuchFieldException, SecurityException {
+  @BeforeEach
+  void setup() throws NoSuchFieldException, SecurityException {
     when(agencyServiceApiControllerFactory.createControllerApi()).thenReturn(agencyControllerApi);
     this.agencyResponseDTOS =
         AGENCY_DTO_LIST.stream().map(this::toAgencyResponseDTO).collect(Collectors.toList());
@@ -72,7 +75,7 @@ private AgencyResponseDTO toAgencyResponseDTO(AgencyDTO agencyDTO) {
   }
 
   @Test
-  public void getAgencies_Should_ReturnAgencyDTOList_When_ProvidedWithValidAgencyIds() {
+  void getAgencies_Should_ReturnAgencyDTOList_When_ProvidedWithValidAgencyIds() {
     when(agencyControllerApi.getAgenciesByIds(ArgumentMatchers.any()))
         .thenReturn(this.agencyResponseDTOS);
 
@@ -82,9 +85,8 @@ public void getAgencies_Should_ReturnAgencyDTOList_When_ProvidedWithValidAgencyI
 
   @SuppressWarnings({"unchecked", "rawtypes"})
   @Test
-  public void
-      test_Should_Fail_When_MethodgetAgenciesFromAgencyServiceDoesNotHaveCacheableAnnotation()
-          throws NoSuchMethodException, SecurityException {
+  void test_Should_Fail_When_MethodgetAgenciesFromAgencyServiceDoesNotHaveCacheableAnnotation()
+      throws NoSuchMethodException, SecurityException {
 
     AgencyService agencyService =
         new AgencyService(
@@ -100,7 +102,7 @@ public void getAgencies_Should_ReturnAgencyDTOList_When_ProvidedWithValidAgencyI
   }
 
   @Test
-  public void getAgency_Should_ReturnAgencyDTO_When_ProvidedWithValidAgencyId() {
+  void getAgency_Should_ReturnAgencyDTO_When_ProvidedWithValidAgencyId() {
 
     when(agencyControllerApi.getAgenciesByIds(ArgumentMatchers.any()))
         .thenReturn(this.agencyResponseDTOS);
@@ -111,7 +113,7 @@ public void getAgency_Should_ReturnAgencyDTO_When_ProvidedWithValidAgencyId() {
 
   @SuppressWarnings({"unchecked", "rawtypes"})
   @Test
-  public void test_Should_Fail_When_MethodgetAgencyFromAgencyServiceDoesNotHaveCacheableAnnotation()
+  void test_Should_Fail_When_MethodgetAgencyFromAgencyServiceDoesNotHaveCacheableAnnotation()
       throws NoSuchMethodException, SecurityException {
 
     AgencyService agencyService =
@@ -128,7 +130,7 @@ public void test_Should_Fail_When_MethodgetAgencyFromAgencyServiceDoesNotHaveCac
   }
 
   @Test
-  public void getAgencyWithoutCaching_Should_ReturnAgencyDTO_WhenProvidedWithValidAgencyId() {
+  void getAgencyWithoutCaching_Should_ReturnAgencyDTO_WhenProvidedWithValidAgencyId() {
     when(agencyControllerApi.getAgenciesByIds(ArgumentMatchers.any()))
         .thenReturn(this.agencyResponseDTOS);
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/helper/MailServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/helper/MailServiceTest.java
index ad1d250dd..efa0888b3 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/helper/MailServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/helper/MailServiceTest.java
@@ -16,17 +16,17 @@
 import de.caritas.cob.userservice.mailservice.generated.web.model.ErrorMailDTO;
 import de.caritas.cob.userservice.mailservice.generated.web.model.MailsDTO;
 import java.util.UUID;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class MailServiceTest {
 
   @Mock private Logger logger;
@@ -41,7 +41,7 @@ public class MailServiceTest {
 
   @InjectMocks private MailService mailService;
 
-  @Before
+  @BeforeEach
   public void setup() throws NoSuchFieldException, SecurityException {
     setInternalState(MailService.class, "log", logger);
     when(mailServiceApiControllerFactory.createControllerApi()).thenReturn(mailsControllerApi);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/helper/RocketChatCredentialsProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/service/helper/RocketChatCredentialsProviderTest.java
index d44673e7d..8eedaca25 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/helper/RocketChatCredentialsProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/helper/RocketChatCredentialsProviderTest.java
@@ -18,11 +18,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.TECHNICAL_USER_B_ID;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.TECHNICAL_USER_B_TOKEN;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.TECHNICAL_USER_B_USERNAME;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotEquals;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -36,13 +32,13 @@
 import de.caritas.cob.userservice.api.adapters.rocketchat.dto.logout.LogoutResponseDTO;
 import de.caritas.cob.userservice.api.exception.rocketchat.RocketChatUserNotInitializedException;
 import java.util.concurrent.atomic.AtomicReference;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentMatchers;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.http.HttpEntity;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
@@ -53,7 +49,7 @@
 import org.springframework.util.MultiValueMap;
 import org.springframework.web.client.RestTemplate;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocketChatCredentialsProviderTest {
 
   /** FIELD Names */
@@ -134,7 +130,7 @@ public class RocketChatCredentialsProviderTest {
 
   @Mock private RestTemplate restTemplate;
 
-  @Before
+  @BeforeEach
   public void setup() throws NoSuchFieldException {
     setField(rcCredentialHelper, FIELD_NAME_TECHNICAL_USERNAME, TECHNICAL_USER_USERNAME);
     setField(rcCredentialHelper, FIELD_NAME_TECHNICAL_PASSWORD, TECHNICAL_USER_PW);
@@ -383,7 +379,7 @@ public void updateCredentials_Should_LogoutAndReLoginBUsers_WhenAllUsersArePrese
       rcCredentialHelper.getTechnicalUser();
       fail("Expected exception: RocketChatUserNotInitializedException");
     } catch (RocketChatUserNotInitializedException ex) {
-      assertTrue("Excepted RocketChatUserNotInitializedException thrown", true);
+      assertTrue(true, "Excepted RocketChatUserNotInitializedException thrown");
     }
   }
 
@@ -455,7 +451,7 @@ public void getTechnicalUser_Should_ReturnUserB_WhenUserBIsNewer() throws Except
       rcCredentialHelper.getSystemUser();
       fail("Expected exception: RocketChatUserNotInitializedException");
     } catch (RocketChatUserNotInitializedException ex) {
-      assertTrue("Excepted RocketChatUserNotInitializedException thrown", true);
+      assertTrue(true, "Excepted RocketChatUserNotInitializedException thrown");
     }
   }
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/helper/RocketChatRollbackServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/helper/RocketChatRollbackServiceTest.java
index f4f43ddde..a0965f082 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/helper/RocketChatRollbackServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/helper/RocketChatRollbackServiceTest.java
@@ -17,16 +17,16 @@
 import de.caritas.cob.userservice.api.exception.rocketchat.RocketChatLeaveFromGroupException;
 import java.util.Arrays;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RocketChatRollbackServiceTest {
 
   private final String MEMBER_ID = "asdkds9";
@@ -51,7 +51,7 @@ public class RocketChatRollbackServiceTest {
   @Mock Logger logger;
   @Mock private RocketChatCredentialsProvider rcCredentialHelper;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(RocketChatRollbackService.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/httpheader/SecurityHeaderSupplierTest.java b/src/test/java/de/caritas/cob/userservice/api/service/httpheader/SecurityHeaderSupplierTest.java
index 144de3b3e..4ad8776c3 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/httpheader/SecurityHeaderSupplierTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/httpheader/SecurityHeaderSupplierTest.java
@@ -3,22 +3,22 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.startsWith;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.mockito.Mockito.when;
 import static org.springframework.test.util.ReflectionTestUtils.setField;
 
 import de.caritas.cob.userservice.api.helper.AuthenticatedUser;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class SecurityHeaderSupplierTest {
 
   private final String CSRF_TOKEN_HEADER_VALUE = "X-CSRF-TOKEN";
@@ -28,7 +28,7 @@ public class SecurityHeaderSupplierTest {
   @InjectMocks private SecurityHeaderSupplier securityHeaderSupplier;
   @Mock private AuthenticatedUser authenticatedUser;
 
-  @Before
+  @BeforeEach
   public void setup() throws NoSuchFieldException, SecurityException {
     setField(securityHeaderSupplier, "csrfHeaderProperty", CSRF_TOKEN_HEADER_VALUE);
     setField(securityHeaderSupplier, "csrfCookieProperty", CSRF_TOKEN_COOKIE_VALUE);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/liveevents/LiveEventNotificationServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/liveevents/LiveEventNotificationServiceTest.java
index 881b4d64a..2fde9b046 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/liveevents/LiveEventNotificationServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/liveevents/LiveEventNotificationServiceTest.java
@@ -6,7 +6,7 @@
 import static java.util.Arrays.asList;
 import static java.util.Collections.emptyList;
 import static java.util.Collections.singletonList;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.doThrow;
@@ -26,16 +26,19 @@
 import de.caritas.cob.userservice.liveservice.generated.web.model.StatusSource;
 import de.caritas.cob.userservice.liveservice.generated.web.model.StatusSource.FinishConversationPhaseEnum;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
 public class LiveEventNotificationServiceTest {
 
   private static final LiveEventMessage MESSAGE = new LiveEventMessage().eventType(DIRECTMESSAGE);
@@ -58,7 +61,7 @@ public class LiveEventNotificationServiceTest {
 
   @Mock private LiveServiceApiControllerFactory liveServiceApiControllerFactory;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(LiveEventNotificationService.class, "log", logger);
     when(liveServiceApiControllerFactory.createControllerApi()).thenReturn(liveControllerApi);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/liveevents/RelevantUserAccountIdsByChatProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/service/liveevents/RelevantUserAccountIdsByChatProviderTest.java
index 9b44f7046..daadae433 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/liveevents/RelevantUserAccountIdsByChatProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/liveevents/RelevantUserAccountIdsByChatProviderTest.java
@@ -18,14 +18,17 @@
 import java.util.Optional;
 import org.apache.commons.lang3.RandomStringUtils;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 
-@RunWith(MockitoJUnitRunner.class)
-public class RelevantUserAccountIdsByChatProviderTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class RelevantUserAccountIdsByChatProviderTest {
 
   private static final EasyRandom easyRandom = new EasyRandom();
 
@@ -38,7 +41,7 @@ public class RelevantUserAccountIdsByChatProviderTest {
   @Mock private ConsultantService consultantService;
 
   @Test
-  public void collectUserIds_Should_returnAllMergedDependingIds_When_rcGroupHasMembers() {
+  void collectUserIds_Should_returnAllMergedDependingIds_When_rcGroupHasMembers() {
     List<GroupMemberDTO> groupMembers =
         asList(memberDTOWithRcId("rc1"), memberDTOWithRcId("rc2"), memberDTOWithRcId("rc3"));
     when(this.rocketChatService.getChatUsers(any())).thenReturn(groupMembers);
@@ -81,7 +84,7 @@ private User userWithId(String userId) {
   }
 
   @Test
-  public void
+  void
       collectUserIds_Should_returnAllMergedDependingIdsInsteadOfNotAvailableUser_When_rcGroupHasMembers() {
     List<GroupMemberDTO> groupMembers =
         asList(memberDTOWithRcId("rc1"), memberDTOWithRcId("rc2"), memberDTOWithRcId("rc3"));
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/liveevents/RelevantUserAccountIdsBySessionProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/service/liveevents/RelevantUserAccountIdsBySessionProviderTest.java
index b5d2664a4..fb518fbfe 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/liveevents/RelevantUserAccountIdsBySessionProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/liveevents/RelevantUserAccountIdsBySessionProviderTest.java
@@ -13,13 +13,13 @@
 import java.util.List;
 import java.util.Optional;
 import org.apache.commons.lang3.RandomStringUtils;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RelevantUserAccountIdsBySessionProviderTest {
 
   @InjectMocks private RelevantUserAccountIdsBySessionProvider bySessionProvider;
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/liveevents/UserIdsProviderFactoryTest.java b/src/test/java/de/caritas/cob/userservice/api/service/liveevents/UserIdsProviderFactoryTest.java
index e81a4b662..991884656 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/liveevents/UserIdsProviderFactoryTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/liveevents/UserIdsProviderFactoryTest.java
@@ -8,13 +8,13 @@
 
 import de.caritas.cob.userservice.api.port.out.ChatRepository;
 import java.util.Optional;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class UserIdsProviderFactoryTest {
 
   @InjectMocks private UserIdsProviderFactory userIdsProviderFactory;
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/message/MessageServiceProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/service/message/MessageServiceProviderTest.java
index 9132623ac..bf801e395 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/message/MessageServiceProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/message/MessageServiceProviderTest.java
@@ -11,10 +11,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER;
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
@@ -43,19 +40,22 @@
 import de.caritas.cob.userservice.messageservice.generated.web.model.MessageDTO;
 import de.caritas.cob.userservice.messageservice.generated.web.model.MessageType;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 import org.springframework.http.HttpHeaders;
-import org.springframework.util.StringUtils;
+import org.springframework.util.ObjectUtils;
 import org.springframework.web.client.RestClientException;
 
-@RunWith(MockitoJUnitRunner.class)
-public class MessageServiceProviderTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class MessageServiceProviderTest {
 
   @InjectMocks private MessageServiceProvider messageServiceProvider;
 
@@ -75,13 +75,13 @@ public class MessageServiceProviderTest {
 
   @Mock private MessageServiceApiControllerFactory messageServiceApiControllerFactory;
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void setUp() {
     when(messageServiceApiControllerFactory.createControllerApi()).thenReturn(messageControllerApi);
   }
 
   @Test
-  public void
+  void
       postEnquiryMessage_Should_ThrowRocketChatPostMessageExceptionWithExceptionInformation_When_PostRcMessageFails() {
     CreateEnquiryExceptionInformation exceptionInformation =
         mock(CreateEnquiryExceptionInformation.class);
@@ -96,13 +96,13 @@ public void setUp() {
       this.messageServiceProvider.postEnquiryMessage(rocketChatData, exceptionInformation);
       fail("Expected exception: RocketChatPostMessageException");
     } catch (RocketChatPostMessageException exception) {
-      assertTrue("Excepted RocketChatPostMessageException thrown", true);
+      assertTrue(true, "Excepted RocketChatPostMessageException thrown");
       assertNotNull(exception.getExceptionInformation());
     }
   }
 
   @Test
-  public void
+  void
       postEnquiryMessage_Should_CallCreateMessageFromMessageServiceWithCorrectParams_When_EverythingSucceeds()
           throws RocketChatPostMessageException {
     CreateEnquiryExceptionInformation exceptionInformation =
@@ -124,9 +124,8 @@ public void setUp() {
   }
 
   @Test
-  public void
-      postWelcomeMessageIfConfigured_ShouldNot_CallMessageService_When_NoWelcomeMessageConfigured()
-          throws RocketChatPostWelcomeMessageException {
+  void postWelcomeMessageIfConfigured_ShouldNot_CallMessageService_When_NoWelcomeMessageConfigured()
+      throws RocketChatPostWelcomeMessageException {
     CreateEnquiryExceptionInformation exceptionInformation =
         mock(CreateEnquiryExceptionInformation.class);
 
@@ -138,7 +137,7 @@ public void setUp() {
   }
 
   @Test
-  public void
+  void
       postWelcomeMessageIfConfigured_Should_ThrowRocketChatPostMessageExceptionWithExceptionInformation_When_GetSystemUserFails()
           throws RocketChatUserNotInitializedException {
     CreateEnquiryExceptionInformation exceptionInformation =
@@ -150,13 +149,13 @@ public void setUp() {
           RC_GROUP_ID, USER, CONSULTING_TYPE_SETTINGS_U25, exceptionInformation);
       fail("Expected exception: RocketChatPostWelcomeMessageException");
     } catch (RocketChatPostWelcomeMessageException exception) {
-      assertTrue("Excepted RocketChatPostWelcomeMessageException thrown", true);
+      assertTrue(true, "Excepted RocketChatPostWelcomeMessageException thrown");
       assertNotNull(exception.getExceptionInformation());
     }
   }
 
   @Test
-  public void
+  void
       postWelcomeMessageIfConfigured_Should_ThrowRocketChatPostMessageExceptionWithExceptionInformation_When_PostRcMessageFails()
           throws RocketChatUserNotInitializedException {
     CreateEnquiryExceptionInformation exceptionInformation =
@@ -174,13 +173,13 @@ public void setUp() {
           RC_GROUP_ID, USER, CONSULTING_TYPE_SETTINGS_U25, exceptionInformation);
       fail("Expected exception: RocketChatPostWelcomeMessageException");
     } catch (RocketChatPostWelcomeMessageException exception) {
-      assertTrue("Excepted RocketChatPostWelcomeMessageException thrown", true);
+      assertTrue(true, "Excepted RocketChatPostWelcomeMessageException thrown");
       assertNotNull(exception.getExceptionInformation());
     }
   }
 
   @Test
-  public void
+  void
       postWelcomeMessageIfConfigured_Should_CallCreateMessageFromMessageServiceWithCorrectParams_When_EverythingSucceeds()
           throws RocketChatUserNotInitializedException, RocketChatPostWelcomeMessageException {
     EasyRandom easyRandom = new EasyRandom();
@@ -200,14 +199,13 @@ public void setUp() {
 
     verify(messageControllerApi)
         .createMessage(anyString(), anyString(), eq(RC_GROUP_ID), captor.capture());
-    assertFalse(StringUtils.isEmpty(USER.getUsername()));
+    assertFalse(ObjectUtils.isEmpty(USER.getUsername()));
     assertThat(captor.getValue().getMessage(), is("Hallo " + USER.getUsername()));
   }
 
   @Test
-  public void
-      postFurtherStepsIfConfigured_ShouldNot_CallMessageService_When_NoFurtherStepsIfConfigured()
-          throws RocketChatPostFurtherStepsMessageException {
+  void postFurtherStepsIfConfigured_ShouldNot_CallMessageService_When_NoFurtherStepsIfConfigured()
+      throws RocketChatPostFurtherStepsMessageException {
     CreateEnquiryExceptionInformation exceptionInformation =
         mock(CreateEnquiryExceptionInformation.class);
 
@@ -219,22 +217,30 @@ public void setUp() {
     verifyNoInteractions(messageControllerApi);
   }
 
-  @Test(expected = RocketChatPostFurtherStepsMessageException.class)
-  public void
+  @Test
+  void
       postFurtherStepsIfConfigured_Should_ThrowRocketChatPostFurtherStepsMessageExceptionWithExceptionInformation_When_PostRcMessageFails()
           throws RocketChatPostFurtherStepsMessageException {
-    CreateEnquiryExceptionInformation exceptionInformation =
-        mock(CreateEnquiryExceptionInformation.class);
-    HttpHeaders headers = mock(HttpHeaders.class);
-    when(securityHeaderSupplier.getKeycloakAndCsrfHttpHeaders()).thenReturn(headers);
-    doThrow(restClientException).when(this.messageControllerApi).saveAliasOnlyMessage(any(), any());
-
-    this.messageServiceProvider.postFurtherStepsIfConfigured(
-        RC_GROUP_ID, CONSULTING_TYPE_SETTINGS_WITH_FURTHER_STEPS_MESSAGE, exceptionInformation);
+    assertThrows(
+        RocketChatPostFurtherStepsMessageException.class,
+        () -> {
+          CreateEnquiryExceptionInformation exceptionInformation =
+              mock(CreateEnquiryExceptionInformation.class);
+          HttpHeaders headers = mock(HttpHeaders.class);
+          when(securityHeaderSupplier.getKeycloakAndCsrfHttpHeaders()).thenReturn(headers);
+          doThrow(restClientException)
+              .when(this.messageControllerApi)
+              .saveAliasOnlyMessage(any(), any());
+
+          this.messageServiceProvider.postFurtherStepsIfConfigured(
+              RC_GROUP_ID,
+              CONSULTING_TYPE_SETTINGS_WITH_FURTHER_STEPS_MESSAGE,
+              exceptionInformation);
+        });
   }
 
   @Test
-  public void postFurtherStepsIfConfigured_Should_SaveFurtherStepsMessage_When_Configured()
+  void postFurtherStepsIfConfigured_Should_SaveFurtherStepsMessage_When_Configured()
       throws RocketChatPostFurtherStepsMessageException {
     CreateEnquiryExceptionInformation exceptionInformation =
         mock(CreateEnquiryExceptionInformation.class);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/mobilepushmessage/FirebasePushMessageServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/mobilepushmessage/FirebasePushMessageServiceTest.java
index 6b1ab81fc..41449272c 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/mobilepushmessage/FirebasePushMessageServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/mobilepushmessage/FirebasePushMessageServiceTest.java
@@ -1,6 +1,7 @@
 package de.caritas.cob.userservice.api.service.mobilepushmessage;
 
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.mock;
@@ -15,15 +16,15 @@
 import com.google.firebase.messaging.FirebaseMessaging;
 import com.google.firebase.messaging.FirebaseMessagingException;
 import de.caritas.cob.userservice.api.service.LogService;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class FirebasePushMessageServiceTest {
 
   @InjectMocks private FirebasePushMessageService firebasePushMessageService;
@@ -32,7 +33,7 @@ public class FirebasePushMessageServiceTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setField(firebasePushMessageService, "firebaseMessaging", firebaseMessaging);
     setInternalState(LogService.class, "LOGGER", logger);
@@ -48,10 +49,14 @@ public void initializeFirebase_Should_notInitialiteFirebaseMessaging_When_fireba
     verify(this.logger, times(1)).info("Firebase push notifications are disabled");
   }
 
-  @Test(expected = Exception.class)
+  @Test
   public void initializeFirebase_Should_throwException_When_configurationCanNotBeLoaded() {
-    setField(this.firebasePushMessageService, "isEnabled", true);
-    this.firebasePushMessageService.initializeFirebase();
+    assertThrows(
+        Exception.class,
+        () -> {
+          setField(this.firebasePushMessageService, "isEnabled", true);
+          this.firebasePushMessageService.initializeFirebase();
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/session/SessionMapperTest.java b/src/test/java/de/caritas/cob/userservice/api/service/session/SessionMapperTest.java
index a7f8722d2..f408e8d5a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/session/SessionMapperTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/session/SessionMapperTest.java
@@ -10,7 +10,7 @@
 import de.caritas.cob.userservice.api.model.Session;
 import java.time.LocalDateTime;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 public class SessionMapperTest {
 
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/session/SessionServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/service/session/SessionServiceIT.java
index 33cfb3de2..1d46e5a0c 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/session/SessionServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/session/SessionServiceIT.java
@@ -27,7 +27,6 @@
 import org.assertj.core.util.Lists;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.extension.ExtendWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
@@ -35,10 +34,8 @@
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.mock.mockito.MockBean;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit.jupiter.SpringExtension;
 import org.springframework.transaction.annotation.Transactional;
 
-@ExtendWith(SpringExtension.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @TestPropertySource(properties = "feature.topics.enabled=true")
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/AvailableLastMessageUpdaterTest.java b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/AvailableLastMessageUpdaterTest.java
index 80460b536..018990f1f 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/AvailableLastMessageUpdaterTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/AvailableLastMessageUpdaterTest.java
@@ -26,14 +26,14 @@
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Consumer;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class AvailableLastMessageUpdaterTest {
 
   private static final String GROUP_ID = "GroupId";
@@ -47,7 +47,7 @@ public class AvailableLastMessageUpdaterTest {
   @Mock private RoomsLastMessageDTO roomsLastMessageDTO;
   private SessionDTO session;
 
-  @Before
+  @BeforeEach
   public void setup() {
     Map<String, RoomsLastMessageDTO> rooms = new HashMap<>();
     rooms.put(GROUP_ID, roomsLastMessageDTO);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantChatEnricherTest.java b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantChatEnricherTest.java
index a791f9bcc..6b421c3ec 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantChatEnricherTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantChatEnricherTest.java
@@ -14,9 +14,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERS_EMPTY_ROOMS_LIST;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERS_ROOMS_LIST;
 import static java.util.Collections.singletonList;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -26,14 +24,14 @@
 import de.caritas.cob.userservice.api.facade.userdata.ConsultantDataFacade;
 import de.caritas.cob.userservice.api.helper.SessionListAnalyser;
 import java.util.List;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class ConsultantChatEnricherTest {
 
   @InjectMocks private ConsultantChatEnricher consultantChatEnricher;
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantSessionEnricherTest.java b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantSessionEnricherTest.java
index 9438d98ce..f10110b01 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantSessionEnricherTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantSessionEnricherTest.java
@@ -24,9 +24,7 @@
 import static java.util.Collections.singletonList;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -40,17 +38,17 @@
 import java.util.Date;
 import java.util.Map;
 import org.jeasy.random.EasyRandom;
-import org.junit.After;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.test.util.ReflectionTestUtils;
 
-@RunWith(MockitoJUnitRunner.class)
-public class ConsultantSessionEnricherTest {
+@ExtendWith(MockitoExtension.class)
+class ConsultantSessionEnricherTest {
 
   @InjectMocks private ConsultantSessionEnricher consultantSessionEnricher;
 
@@ -62,13 +60,13 @@ public class ConsultantSessionEnricherTest {
 
   @Mock private SessionTopicEnrichmentService sessionTopicEnrichmentService;
 
-  @After
-  public void tearDown() {
+  @AfterEach
+  void tearDown() {
     ReflectionTestUtils.setField(consultantSessionEnricher, "topicsFeatureEnabled", false);
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnValidSessionListWithMessagesReadTrue_WhenThereAreNoUnreadMessages() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -95,7 +93,7 @@ public void tearDown() {
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnValidSessionListWithMessagesReadFalse_WhenThereAreUnreadMessages() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -122,7 +120,7 @@ public void tearDown() {
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_EnrichWithTopicsIfTopicFeatureIsEnabled() {
     ReflectionTestUtils.setField(consultantSessionEnricher, "topicsFeatureEnabled", true);
     ReflectionTestUtils.setField(
@@ -155,7 +153,7 @@ public void tearDown() {
   }
 
   @Test
-  public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate() {
+  void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
             .readMessages(MESSAGES_READ_MAP_WITH_UNREADS)
@@ -179,7 +177,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnFalseAsAttachmentReceivedStatus_WhenCallingConsultantIsSenderOfTheAttachment() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -205,7 +203,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnTrueAsAttachmentReceivedStatus_WhenCallingConsultantIsNotSenderOfTheAttachment() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -231,7 +229,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_ShouldNot_SetIsFeedbackReadToFalse_WhenNoMessageWasPostedInTheFeedbackRoom() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -257,7 +255,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_SendListWithMonitoringFalse_When_NoMonitoringSetInConsultingTypeSettings() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -278,7 +276,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_SendListWithMonitoringTrue_When_MonitoringSetInConsultingTypeSettings() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -299,7 +297,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnCorrectFileTypeAndImagePreviewForSession() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -327,7 +325,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnSessionListWithMessagesReadFalse_WhenThereAreUnreadMessages() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -353,7 +351,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnSessionListWithFeedbackReadTrue_WhenThereAreNoUnreadFeedbackMessages() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -379,7 +377,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnMessageDateAsUnixtime0_WhenNoMessages() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -402,7 +400,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnSessionListWithFeedbackReadTrue_WhenFeedbackGroupIdIsNull() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -430,7 +428,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnSessionListWithChatMessagesReadFalse_WhenThereAreUnreadSessionMessages() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -455,7 +453,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnSessionListWithChatMessagesReadTrue_WhenThereAreNoUnreadSessionMessages() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -480,7 +478,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_Should_ReturnMessageDateAsFromCreateDate_When_sessionIsAnonymous() {
     RocketChatRoomInformation rocketChatRoomInformation =
         RocketChatRoomInformation.builder()
@@ -508,7 +506,7 @@ public void updateRequiredConsultantSessionValues_Should_SetCorrectMessageDate()
   }
 
   @Test
-  public void
+  void
       updateRequiredConsultantSessionValues_should_use_fallback_date_if_last_message_is_unavailable() {
     var fallbackDates = Map.of(RC_GROUP_ID, new Date(1655730882738L));
     RocketChatRoomInformation rocketChatRoomInformation =
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantSessionListServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantSessionListServiceTest.java
index 2b6d416c0..218cb39be 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantSessionListServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/ConsultantSessionListServiceTest.java
@@ -14,10 +14,7 @@
 import static java.util.Arrays.asList;
 import static java.util.Objects.nonNull;
 import static org.jsoup.helper.Validate.fail;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertNull;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.never;
@@ -32,16 +29,16 @@
 import de.caritas.cob.userservice.api.service.session.SessionService;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
-public class ConsultantSessionListServiceTest {
+@ExtendWith(MockitoExtension.class)
+class ConsultantSessionListServiceTest {
 
   @InjectMocks private ConsultantSessionListService consultantSessionListService;
   @Mock private SessionService sessionService;
@@ -50,21 +47,18 @@ public class ConsultantSessionListServiceTest {
   @Mock private ConsultantChatEnricher consultantChatEnricher;
   @Mock private RocketChatCredentials rocketChatCredentials;
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void setup() {}
+
+  @Test
+  void
+      retrieveSessionsForAuthenticatedConsultant_Should_ReturnOnlySessions_WhenQueryParameterSessionStatusIsNew() {
+
     when(sessionService.getRegisteredEnquiriesForConsultant(Mockito.any()))
         .thenReturn(CONSULTANT_SESSION_RESPONSE_DTO_LIST);
     when(this.consultantSessionEnricher.updateRequiredConsultantSessionValues(
             eq(CONSULTANT_SESSION_RESPONSE_DTO_LIST), any(), any()))
         .thenReturn(CONSULTANT_SESSION_RESPONSE_DTO_LIST);
-    when(this.consultantChatEnricher.updateRequiredConsultantChatValues(
-            eq(List.of(CONSULTANT_SESSION_RESPONSE_DTO_WITH_ENCRYPTED_CHAT_MESSAGE)), any(), any()))
-        .thenReturn(List.of(CONSULTANT_SESSION_RESPONSE_DTO_WITH_ENCRYPTED_CHAT_MESSAGE));
-  }
-
-  @Test
-  public void
-      retrieveSessionsForAuthenticatedConsultant_Should_ReturnOnlySessions_WhenQueryParameterSessionStatusIsNew() {
     when(rocketChatCredentials.getRocketChatToken()).thenReturn(RC_TOKEN);
 
     List<ConsultantSessionResponseDTO> result =
@@ -81,7 +75,12 @@ public void setup() {
   }
 
   @Test
-  public void retrieveSessionsForAuthenticatedConsultant_ShouldNot_SendChatsInEnquiryList() {
+  void retrieveSessionsForAuthenticatedConsultant_ShouldNot_SendChatsInEnquiryList() {
+    when(sessionService.getRegisteredEnquiriesForConsultant(Mockito.any()))
+        .thenReturn(CONSULTANT_SESSION_RESPONSE_DTO_LIST);
+    when(this.consultantSessionEnricher.updateRequiredConsultantSessionValues(
+            eq(CONSULTANT_SESSION_RESPONSE_DTO_LIST), any(), any()))
+        .thenReturn(CONSULTANT_SESSION_RESPONSE_DTO_LIST);
     when(rocketChatCredentials.getRocketChatToken()).thenReturn(RC_TOKEN);
 
     List<ConsultantSessionResponseDTO> result =
@@ -93,7 +92,14 @@ public void retrieveSessionsForAuthenticatedConsultant_ShouldNot_SendChatsInEnqu
   }
 
   @Test
-  public void retrieveSessionsForAuthenticatedConsultant_Should_MergeSessionsAndChats() {
+  void retrieveSessionsForAuthenticatedConsultant_Should_MergeSessionsAndChats() {
+
+    when(this.consultantSessionEnricher.updateRequiredConsultantSessionValues(
+            eq(CONSULTANT_SESSION_RESPONSE_DTO_LIST), any(), any()))
+        .thenReturn(CONSULTANT_SESSION_RESPONSE_DTO_LIST);
+    when(this.consultantChatEnricher.updateRequiredConsultantChatValues(
+            eq(List.of(CONSULTANT_SESSION_RESPONSE_DTO_WITH_ENCRYPTED_CHAT_MESSAGE)), any(), any()))
+        .thenReturn(List.of(CONSULTANT_SESSION_RESPONSE_DTO_WITH_ENCRYPTED_CHAT_MESSAGE));
     when(chatService.getChatsForConsultant(Mockito.any()))
         .thenReturn(CONSULTANT_SESSION_RESPONSE_DTO_LIST_WITH_ENCRYPTED_CHAT_MESSAGE);
     when(sessionService.getActiveAndDoneSessionsForConsultant(Mockito.any()))
@@ -139,7 +145,7 @@ public void retrieveSessionsForAuthenticatedConsultant_Should_MergeSessionsAndCh
   }
 
   @Test
-  public void
+  void
       retrieveTeamSessionsForAuthenticatedConsultant_Should_ReturnFilteredSessionList_WhenFeedbackFilter() {
     List<ConsultantSessionResponseDTO> responseDTOS =
         new ArrayList<>(
@@ -166,7 +172,7 @@ public void retrieveSessionsForAuthenticatedConsultant_Should_MergeSessionsAndCh
   }
 
   @Test
-  public void
+  void
       retrieveSessionsForAuthenticatedConsultant_Should_returnEmptyList_When_SessionStatusIsInitial() {
     SessionListQueryParameter sessionListQueryParameter =
         createStandardSessionListQueryParameterObject(0);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/UserSessionListServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/UserSessionListServiceTest.java
index 8457180ff..df4ae3acd 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/UserSessionListServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/sessionlist/UserSessionListServiceTest.java
@@ -23,10 +23,7 @@
 import static java.util.Collections.emptyMap;
 import static java.util.Objects.nonNull;
 import static org.jsoup.helper.Validate.fail;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.Mockito.when;
 
 import de.caritas.cob.userservice.api.adapters.web.dto.UserSessionResponseDTO;
@@ -38,14 +35,14 @@
 import de.caritas.cob.userservice.api.service.session.SessionService;
 import java.util.Collections;
 import java.util.List;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class UserSessionListServiceTest {
 
   @InjectMocks private UserSessionListService userSessionListService;
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/statistics/StatisticsServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/service/statistics/StatisticsServiceIT.java
index 81215a44d..0a58c91db 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/statistics/StatisticsServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/statistics/StatisticsServiceIT.java
@@ -15,8 +15,7 @@
 import java.time.OffsetDateTime;
 import java.time.ZoneOffset;
 import org.apache.commons.io.IOUtils;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
 import org.springframework.amqp.core.AmqpTemplate;
 import org.springframework.amqp.core.Message;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -24,9 +23,7 @@
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @SpringBootTest(classes = UserServiceApplication.class)
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/statistics/StatisticsServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/statistics/StatisticsServiceTest.java
index 51ea2e783..d7beff7e8 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/statistics/StatisticsServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/statistics/StatisticsServiceTest.java
@@ -12,20 +12,23 @@
 import de.caritas.cob.userservice.statisticsservice.generated.web.model.EventType;
 import java.nio.charset.StandardCharsets;
 import java.util.Optional;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 import org.slf4j.Logger;
 import org.springframework.amqp.core.AmqpTemplate;
 import org.springframework.amqp.core.MessageBuilder;
 import org.springframework.amqp.core.MessageProperties;
 
-@RunWith(MockitoJUnitRunner.class)
-public class StatisticsServiceTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class StatisticsServiceTest {
 
   private static final String FIELD_NAME_STATISTICS_ENABLED = "statisticsEnabled";
   private static final String FIELD_NAME_RABBIT_EXCHANGE_NAME = "rabbitMqExchangeName";
@@ -39,8 +42,8 @@ public class StatisticsServiceTest {
   @Mock private AmqpTemplate amqpTemplate;
   @Mock Logger logger;
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void setup() {
     assignSessionStatisticsEvent = Mockito.mock(AssignSessionStatisticsEvent.class);
     when(assignSessionStatisticsEvent.getEventType()).thenReturn(eventType);
     when(assignSessionStatisticsEvent.getPayload()).thenReturn(Optional.of(PAYLOAD));
@@ -49,7 +52,7 @@ public void setup() {
   }
 
   @Test
-  public void fireEvent_Should_NotSendStatisticsMessage_WhenStatisticsIsDisabled() {
+  void fireEvent_Should_NotSendStatisticsMessage_WhenStatisticsIsDisabled() {
 
     setField(statisticsService, FIELD_NAME_STATISTICS_ENABLED, false);
     statisticsService.fireEvent(assignSessionStatisticsEvent);
@@ -58,7 +61,7 @@ public void fireEvent_Should_NotSendStatisticsMessage_WhenStatisticsIsDisabled()
   }
 
   @Test
-  public void fireEvent_Should_SendStatisticsMessage_WhenStatisticsIsEnabled() {
+  void fireEvent_Should_SendStatisticsMessage_WhenStatisticsIsEnabled() {
 
     setField(statisticsService, FIELD_NAME_STATISTICS_ENABLED, true);
     when(assignSessionStatisticsEvent.getEventType()).thenReturn(eventType);
@@ -70,7 +73,7 @@ public void fireEvent_Should_SendStatisticsMessage_WhenStatisticsIsEnabled() {
   }
 
   @Test
-  public void fireEvent_Should_LogWarning_WhenPayloadIsEmpty() {
+  void fireEvent_Should_LogWarning_WhenPayloadIsEmpty() {
 
     setField(statisticsService, FIELD_NAME_STATISTICS_ENABLED, true);
     when(assignSessionStatisticsEvent.getPayload()).thenReturn(Optional.empty());
@@ -79,7 +82,7 @@ public void fireEvent_Should_LogWarning_WhenPayloadIsEmpty() {
   }
 
   @Test
-  public void fireEvent_Should_UseEventTypeAsTopicAndSendPayloadOfEvent() {
+  void fireEvent_Should_UseEventTypeAsTopicAndSendPayloadOfEvent() {
 
     setField(statisticsService, FIELD_NAME_STATISTICS_ENABLED, true);
     statisticsService.fireEvent(assignSessionStatisticsEvent);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/statistics/event/AssignSessionStatisticsEventTest.java b/src/test/java/de/caritas/cob/userservice/api/service/statistics/event/AssignSessionStatisticsEventTest.java
index 9b205d3b8..5aaf611bc 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/statistics/event/AssignSessionStatisticsEventTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/statistics/event/AssignSessionStatisticsEventTest.java
@@ -11,17 +11,17 @@
 import java.time.OffsetDateTime;
 import java.time.ZoneOffset;
 import java.util.Optional;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class AssignSessionStatisticsEventTest {
 
   private AssignSessionStatisticsEvent assignSessionStatisticsEvent;
 
-  @Before
+  @BeforeEach
   public void setup() throws NoSuchFieldException, IllegalAccessException {
     assignSessionStatisticsEvent =
         new AssignSessionStatisticsEvent(CONSULTANT_ID, UserRole.CONSULTANT, SESSION_ID);
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/statistics/event/RegistrationStatisticsEventTest.java b/src/test/java/de/caritas/cob/userservice/api/service/statistics/event/RegistrationStatisticsEventTest.java
index 9febf0a07..4a8c21ae7 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/statistics/event/RegistrationStatisticsEventTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/statistics/event/RegistrationStatisticsEventTest.java
@@ -14,17 +14,17 @@
 import java.time.LocalDateTime;
 import java.util.List;
 import java.util.Optional;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class RegistrationStatisticsEventTest {
 
   private RegistrationStatisticsEvent registrationStatisticsEvent;
 
-  @Before
+  @BeforeEach
   public void setUp() {
     UserDTO registeredUser =
         UserDTO.builder()
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/user/UserAccountServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/service/user/UserAccountServiceTest.java
index 05e2336c9..a09a08153 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/user/UserAccountServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/user/UserAccountServiceTest.java
@@ -4,7 +4,8 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USER_ID;
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.mock;
@@ -35,15 +36,15 @@
 import java.util.Optional;
 import org.apache.commons.lang3.RandomStringUtils;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class UserAccountServiceTest {
 
   private static final EasyRandom EASY_RANDOM = new EasyRandom();
@@ -109,12 +110,16 @@ public void retrieveValidatedUser_Should_ReturnUser_When_UserIsPresent() {
     assertThat(resultUser).isEqualTo(userMock);
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       retrieveValidatedUser_Should_Throw_InternalServerErrorException_When_UserIsNotPresent() {
-    when(userService.getUser(any())).thenReturn(Optional.empty());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(userService.getUser(any())).thenReturn(Optional.empty());
 
-    this.accountProvider.retrieveValidatedUser();
+          this.accountProvider.retrieveValidatedUser();
+        });
   }
 
   @Test
@@ -127,12 +132,16 @@ public void retrieveValidatedConsultant_Should_ReturnConsultant_When_ConsultantI
     assertThat(resultUser).isEqualTo(consultantMock);
   }
 
-  @Test(expected = InternalServerErrorException.class)
+  @Test
   public void
       retrieveValidatedConsultant_Should_Throw_InternalServerErrorException_When_ConsultantIsNotPresent() {
-    when(consultantService.getConsultant(any())).thenReturn(Optional.empty());
+    assertThrows(
+        InternalServerErrorException.class,
+        () -> {
+          when(consultantService.getConsultant(any())).thenReturn(Optional.empty());
 
-    this.accountProvider.retrieveValidatedConsultant();
+          this.accountProvider.retrieveValidatedConsultant();
+        });
   }
 
   @Test
@@ -147,13 +156,17 @@ public void retrieveValidatedConsultant_Should_ReturnConsultant_When_ConsultantI
     assertThat(resultUser).isEqualTo(teamConsultantMock);
   }
 
-  @Test(expected = ForbiddenException.class)
+  @Test
   public void
       retrieveValidatedTeamConsultant_Should_Throw_ForbiddenException_When_ConsultantIsNotATeamConsultant() {
-    Consultant consultantMock = mock(Consultant.class);
-    when(consultantService.getConsultant(any())).thenReturn(Optional.of(consultantMock));
-
-    this.accountProvider.retrieveValidatedTeamConsultant();
+    assertThrows(
+        ForbiddenException.class,
+        () -> {
+          Consultant consultantMock = mock(Consultant.class);
+          when(consultantService.getConsultant(any())).thenReturn(Optional.of(consultantMock));
+
+          this.accountProvider.retrieveValidatedTeamConsultant();
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/user/UserServiceIT.java b/src/test/java/de/caritas/cob/userservice/api/service/user/UserServiceIT.java
index c9faed926..88b5296e1 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/user/UserServiceIT.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/user/UserServiceIT.java
@@ -11,15 +11,12 @@
 import de.caritas.cob.userservice.api.port.out.UserRepository;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
-import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
 import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase.Replace;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.TestPropertySource;
-import org.springframework.test.context.junit4.SpringRunner;
 
-@RunWith(SpringRunner.class)
 @SpringBootTest(classes = UserServiceApplication.class)
 @TestPropertySource(properties = "spring.profiles.active=testing")
 @AutoConfigureTestDatabase(replace = Replace.ANY)
diff --git a/src/test/java/de/caritas/cob/userservice/api/service/user/validation/UserAccountValidatorTest.java b/src/test/java/de/caritas/cob/userservice/api/service/user/validation/UserAccountValidatorTest.java
index ae06121d2..6733a5b2a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/service/user/validation/UserAccountValidatorTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/service/user/validation/UserAccountValidatorTest.java
@@ -3,6 +3,7 @@
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.ERROR;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.PASSWORD;
 import static de.caritas.cob.userservice.api.testHelper.TestConstants.USERNAME;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -12,24 +13,28 @@
 import de.caritas.cob.userservice.api.exception.httpresponses.BadRequestException;
 import de.caritas.cob.userservice.api.port.out.IdentityClient;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
 
-@RunWith(SpringRunner.class)
+@ExtendWith(SpringExtension.class)
 public class UserAccountValidatorTest {
 
   @InjectMocks private UserAccountValidator userAccountValidator;
   @Mock private IdentityClient identityClient;
 
-  @Test(expected = BadRequestException.class)
+  @Test
   public void checkPasswordValidity_Should_ThrowBadRequestException_When_KeycloakLoginFails() {
-    when(identityClient.loginUser(anyString(), anyString()))
-        .thenThrow(new BadRequestException(ERROR));
-
-    this.userAccountValidator.checkPasswordValidity(USERNAME, PASSWORD);
+    assertThrows(
+        BadRequestException.class,
+        () -> {
+          when(identityClient.loginUser(anyString(), anyString()))
+              .thenThrow(new BadRequestException(ERROR));
+
+          this.userAccountValidator.checkPasswordValidity(USERNAME, PASSWORD);
+        });
   }
 
   @Test
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAppointmentServiceAskerActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAppointmentServiceAskerActionTest.java
index c8513e2fd..7ebab2bcc 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAppointmentServiceAskerActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAppointmentServiceAskerActionTest.java
@@ -21,15 +21,15 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteAppointmentServiceAskerActionTest {
 
   @InjectMocks private DeleteAppointmentServiceAskerAction deleteAppointmentServiceAskerAction;
@@ -38,7 +38,7 @@ public class DeleteAppointmentServiceAskerActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteAppointmentServiceAskerAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAskerRoomsAndSessionsActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAskerRoomsAndSessionsActionTest.java
index c2ddb6e14..6d1a6b570 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAskerRoomsAndSessionsActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteAskerRoomsAndSessionsActionTest.java
@@ -30,15 +30,15 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteAskerRoomsAndSessionsActionTest {
 
   @InjectMocks private DeleteAskerRoomsAndSessionsAction deleteAskerRoomsAndSessionsAction;
@@ -51,7 +51,7 @@ public class DeleteAskerRoomsAndSessionsActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteAskerRoomsAndSessionsAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteDatabaseAskerActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteDatabaseAskerActionTest.java
index 6d7eb4336..ed124f000 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteDatabaseAskerActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteDatabaseAskerActionTest.java
@@ -21,15 +21,15 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteDatabaseAskerActionTest {
 
   @InjectMocks private DeleteDatabaseAskerAction deleteDatabaseAskerAction;
@@ -38,7 +38,7 @@ public class DeleteDatabaseAskerActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteDatabaseAskerAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteDatabaseAskerAgencyActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteDatabaseAskerAgencyActionTest.java
index 00f93f8a5..5ed2c51e8 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteDatabaseAskerAgencyActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteDatabaseAskerAgencyActionTest.java
@@ -20,15 +20,15 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteDatabaseAskerAgencyActionTest {
 
   @InjectMocks private DeleteDatabaseAskerAgencyAction deleteDatabaseAskerAgencyAction;
@@ -37,7 +37,7 @@ public class DeleteDatabaseAskerAgencyActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteDatabaseAskerAgencyAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteKeycloakAskerActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteKeycloakAskerActionTest.java
index 7eb6dd913..84507f3e7 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteKeycloakAskerActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteKeycloakAskerActionTest.java
@@ -21,17 +21,17 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 import org.springframework.http.HttpStatus;
 import org.springframework.web.client.HttpClientErrorException;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteKeycloakAskerActionTest {
 
   @InjectMocks private DeleteKeycloakAskerAction deleteKeycloakAskerAction;
@@ -40,7 +40,7 @@ public class DeleteKeycloakAskerActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteKeycloakAskerAction.class, "log", logger);
     setInternalState(DeleteKeycloakUserAction.class, "log", logger);
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteRocketChatAskerActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteRocketChatAskerActionTest.java
index cde25bad1..b31f37447 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteRocketChatAskerActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteRocketChatAskerActionTest.java
@@ -22,15 +22,15 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteRocketChatAskerActionTest {
 
   @InjectMocks private DeleteRocketChatAskerAction deleteRocketChatAskerAction;
@@ -39,7 +39,7 @@ public class DeleteRocketChatAskerActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteRocketChatAskerAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteSingleRoomAndSessionActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteSingleRoomAndSessionActionTest.java
index 38ba85126..2a5199e88 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteSingleRoomAndSessionActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/asker/DeleteSingleRoomAndSessionActionTest.java
@@ -26,15 +26,15 @@
 import java.util.ArrayList;
 import java.util.List;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteSingleRoomAndSessionActionTest {
 
   @InjectMocks private DeleteSingleRoomAndSessionAction deleteSingleRoomAndSessionAction;
@@ -47,7 +47,7 @@ public class DeleteSingleRoomAndSessionActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteSingleRoomAndSessionAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteAppointmentServiceConsultantActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteAppointmentServiceConsultantActionTest.java
index 898b89615..81f2a5277 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteAppointmentServiceConsultantActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteAppointmentServiceConsultantActionTest.java
@@ -21,15 +21,15 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteAppointmentServiceConsultantActionTest {
 
   @InjectMocks
@@ -39,7 +39,7 @@ public class DeleteAppointmentServiceConsultantActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteAppointmentServiceConsultantAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteChatActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteChatActionTest.java
index 4c2b42578..b659c9a18 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteChatActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteChatActionTest.java
@@ -29,15 +29,15 @@
 import java.util.List;
 import java.util.stream.Collectors;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteChatActionTest {
 
   @InjectMocks private DeleteChatAction deleteChatAction;
@@ -48,7 +48,7 @@ public class DeleteChatActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteChatAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteDatabaseConsultantActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteDatabaseConsultantActionTest.java
index 5ea89de31..7fe597b0a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteDatabaseConsultantActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteDatabaseConsultantActionTest.java
@@ -7,7 +7,7 @@
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
-import static org.junit.Assert.assertNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.Mockito.doThrow;
@@ -25,15 +25,15 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteDatabaseConsultantActionTest {
 
   @InjectMocks private DeleteDatabaseConsultantAction deleteDatabaseConsultantAction;
@@ -44,7 +44,7 @@ public class DeleteDatabaseConsultantActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteDatabaseConsultantAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteDatabaseConsultantAgencyActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteDatabaseConsultantAgencyActionTest.java
index d19afe6d6..335d8ecb5 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteDatabaseConsultantAgencyActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteDatabaseConsultantAgencyActionTest.java
@@ -20,15 +20,15 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteDatabaseConsultantAgencyActionTest {
 
   @InjectMocks private DeleteDatabaseConsultantAgencyAction deleteDatabaseConsultantAgencyAction;
@@ -37,7 +37,7 @@ public class DeleteDatabaseConsultantAgencyActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteDatabaseConsultantAgencyAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteKeycloakConsultantActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteKeycloakConsultantActionTest.java
index 6d1a279cc..621f5c199 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteKeycloakConsultantActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteKeycloakConsultantActionTest.java
@@ -21,17 +21,17 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 import org.springframework.http.HttpStatus;
 import org.springframework.web.client.HttpClientErrorException;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteKeycloakConsultantActionTest {
 
   @InjectMocks private DeleteKeycloakConsultantAction deleteKeycloakConsultantAction;
@@ -40,7 +40,7 @@ public class DeleteKeycloakConsultantActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteKeycloakConsultantAction.class, "log", logger);
     setInternalState(DeleteKeycloakUserAction.class, "log", logger);
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteRocketChatConsultantActionTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteRocketChatConsultantActionTest.java
index c2f9c5e0d..337d292a4 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteRocketChatConsultantActionTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/action/consultant/DeleteRocketChatConsultantActionTest.java
@@ -22,15 +22,15 @@
 import de.caritas.cob.userservice.api.workflow.delete.model.DeletionWorkflowError;
 import java.util.ArrayList;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteRocketChatConsultantActionTest {
 
   @InjectMocks private DeleteRocketChatConsultantAction deleteRocketChatConsultantAction;
@@ -39,7 +39,7 @@ public class DeleteRocketChatConsultantActionTest {
 
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(DeleteRocketChatConsultantAction.class, "log", logger);
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteInactiveSessionsAndUserSchedulerTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteInactiveSessionsAndUserSchedulerTest.java
index 597c158c5..38b9e506a 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteInactiveSessionsAndUserSchedulerTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteInactiveSessionsAndUserSchedulerTest.java
@@ -6,13 +6,13 @@
 
 import de.caritas.cob.userservice.api.tenant.TenantContextProvider;
 import de.caritas.cob.userservice.api.workflow.delete.service.DeleteInactiveSessionsAndUserService;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteInactiveSessionsAndUserSchedulerTest {
 
   private final String FIELD_NAME_SESSION_INACTIVE_DELETE_WORKFLOW_ENABLED =
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUserAccountSchedulerTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUserAccountSchedulerTest.java
index efd128a9c..957748e0d 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUserAccountSchedulerTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUserAccountSchedulerTest.java
@@ -4,13 +4,13 @@
 
 import de.caritas.cob.userservice.api.tenant.TenantContextProvider;
 import de.caritas.cob.userservice.api.workflow.delete.service.DeleteUserAccountService;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteUserAccountSchedulerTest {
 
   @InjectMocks private DeleteUserAccountScheduler deleteUserAccountScheduler;
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUserAnonymousSchedulerTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUserAnonymousSchedulerTest.java
index 781c29109..2963e32bf 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUserAnonymousSchedulerTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUserAnonymousSchedulerTest.java
@@ -4,13 +4,13 @@
 
 import de.caritas.cob.userservice.api.tenant.TenantContextProvider;
 import de.caritas.cob.userservice.api.workflow.delete.service.DeleteUserAnonymousService;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteUserAnonymousSchedulerTest {
 
   @InjectMocks private DeleteUserAnonymousScheduler deleteUserAnonymousScheduler;
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUsersRegisteredOnlySchedulerTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUsersRegisteredOnlySchedulerTest.java
index c57b3364c..5c0ded6ee 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUsersRegisteredOnlySchedulerTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/scheduler/DeleteUsersRegisteredOnlySchedulerTest.java
@@ -6,13 +6,13 @@
 
 import de.caritas.cob.userservice.api.tenant.TenantContextProvider;
 import de.caritas.cob.userservice.api.workflow.delete.service.DeleteUsersRegisteredOnlyService;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteUsersRegisteredOnlySchedulerTest {
 
   @InjectMocks DeleteUsersRegisteredOnlyScheduler deleteUsersRegisteredOnlyScheduler;
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteInactiveSessionsAndUserServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteInactiveSessionsAndUserServiceTest.java
index 92b1a151e..383a2338e 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteInactiveSessionsAndUserServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteInactiveSessionsAndUserServiceTest.java
@@ -21,14 +21,14 @@
 import java.util.Map;
 import java.util.Optional;
 import org.jeasy.random.EasyRandom;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteInactiveSessionsAndUserServiceTest {
 
   @InjectMocks private DeleteInactiveSessionsAndUserService deleteInactiveSessionsAndUserService;
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteSessionServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteSessionServiceTest.java
index 3a4e21c74..8c0bbd5c9 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteSessionServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteSessionServiceTest.java
@@ -13,13 +13,13 @@
 import de.caritas.cob.userservice.api.model.Session;
 import de.caritas.cob.userservice.api.workflow.delete.action.asker.DeleteSingleRoomAndSessionAction;
 import de.caritas.cob.userservice.api.workflow.delete.model.SessionDeletionWorkflowDTO;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteSessionServiceTest {
 
   @InjectMocks private DeleteSessionService deleteSessionService;
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteUserAccountServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteUserAccountServiceTest.java
index a6e4e57ca..4bbc8e8bc 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteUserAccountServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteUserAccountServiceTest.java
@@ -25,13 +25,13 @@
 import de.caritas.cob.userservice.api.workflow.delete.action.consultant.DeleteRocketChatConsultantAction;
 import de.caritas.cob.userservice.api.workflow.delete.model.AskerDeletionWorkflowDTO;
 import de.caritas.cob.userservice.api.workflow.delete.model.ConsultantDeletionWorkflowDTO;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteUserAccountServiceTest {
 
   @InjectMocks private DeleteUserAccountService deleteUserAccountService;
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteUsersRegisteredOnlyServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteUsersRegisteredOnlyServiceTest.java
index 25bb2c986..cf16ad20e 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteUsersRegisteredOnlyServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/DeleteUsersRegisteredOnlyServiceTest.java
@@ -17,14 +17,14 @@
 import java.time.LocalDateTime;
 import java.time.LocalTime;
 import java.util.Collections;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.Mockito;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class DeleteUsersRegisteredOnlyServiceTest {
 
   @InjectMocks private DeleteUsersRegisteredOnlyService deleteUsersRegisteredOnlyService;
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/WorkflowErrorLogServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/WorkflowErrorLogServiceTest.java
index 43274c0e5..2a6e54b3b 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/WorkflowErrorLogServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/WorkflowErrorLogServiceTest.java
@@ -12,21 +12,21 @@
 import java.util.ArrayList;
 import java.util.List;
 import org.assertj.core.api.Assertions;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.LoggerFactory;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class WorkflowErrorLogServiceTest {
 
   @InjectMocks private WorkflowErrorLogService workflowErrorLogService;
 
   private ListAppender<ILoggingEvent> listAppender;
 
-  @Before
+  @BeforeEach
   public void setUp() {
     Logger logger = (Logger) LoggerFactory.getLogger(WorkflowErrorLogService.class);
     listAppender = new ListAppender<>();
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/WorkflowErrorMailServiceTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/WorkflowErrorMailServiceTest.java
index 0f6157f12..d935bfc07 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/WorkflowErrorMailServiceTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/WorkflowErrorMailServiceTest.java
@@ -19,16 +19,16 @@
 import de.caritas.cob.userservice.mailservice.generated.web.model.ErrorMailDTO;
 import de.caritas.cob.userservice.mailservice.generated.web.model.TemplateDataDTO;
 import java.util.List;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.springframework.test.util.ReflectionTestUtils;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class WorkflowErrorMailServiceTest {
 
   @InjectMocks private WorkflowErrorMailService workflowErrorMailService;
@@ -37,7 +37,7 @@ public class WorkflowErrorMailServiceTest {
 
   @Mock private TenantTemplateSupplier tenantTemplateSupplier;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setField(workflowErrorMailService, "applicationBaseUrl", "www.host.de");
   }
diff --git a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/provider/InactivePrivateGroupsProviderTest.java b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/provider/InactivePrivateGroupsProviderTest.java
index 441ef4b50..85d1a71aa 100644
--- a/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/provider/InactivePrivateGroupsProviderTest.java
+++ b/src/test/java/de/caritas/cob/userservice/api/workflow/delete/service/provider/InactivePrivateGroupsProviderTest.java
@@ -26,15 +26,15 @@
 import java.util.List;
 import org.apache.commons.collections4.IterableUtils;
 import org.jeasy.random.EasyRandom;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnitRunner;
+import org.mockito.junit.jupiter.MockitoExtension;
 import org.slf4j.Logger;
 
-@RunWith(MockitoJUnitRunner.class)
+@ExtendWith(MockitoExtension.class)
 public class InactivePrivateGroupsProviderTest {
 
   @InjectMocks private InactivePrivateGroupsProvider inactivePrivateGroupsProvider;
@@ -43,7 +43,7 @@ public class InactivePrivateGroupsProviderTest {
   @Mock private ChatRepository chatRepository;
   @Mock private Logger logger;
 
-  @Before
+  @BeforeEach
   public void setup() {
     setInternalState(LogService.class, "LOGGER", logger);
   }