diff --git a/src/main/java/com/MeetMate/company/CompanyService.java b/src/main/java/com/MeetMate/company/CompanyService.java
index 45dad12..a10399c 100644
--- a/src/main/java/com/MeetMate/company/CompanyService.java
+++ b/src/main/java/com/MeetMate/company/CompanyService.java
@@ -118,10 +118,16 @@ public void addMember(String token, String memberEmail, String memberName, Strin
 
     Query query = new Query(Criteria.where("ownerEmail").is(company.getOwnerEmail()));
     Update update = new Update();
-    ArrayList<Long> a = company.getMemberIds();
-    a.add(userRepository.findUserByEmail(memberEmail)
+
+    Long memberId = userRepository.findUserByEmail(memberEmail)
         .orElseThrow(() -> new IllegalStateException("Member could not be created correctly!"))
-        .getId());
+        .getId();
+
+    ArrayList<Long> a = company.getMemberIds();
+    if (a.contains(memberId))
+      throw new IllegalStateException("Member already exists");
+
+    a.add(memberId);
     update.set("memberIds", a);
 
     mongoTemplate.updateFirst(query, update, Company.class);
@@ -134,7 +140,18 @@ public void deleteMember(String token, long memberId) throws IllegalAccessExcept
     if (!isCompanyMember(company, memberId))
       throw new IllegalAccessException("Not a member of the company");
 
-    userRepository.deleteById(memberId);
+    User member = userRepository.findUserById(memberId)
+        .orElseThrow(() -> new EntityNotFoundException("Member not found"));
+
+    userRepository.delete(member);
+
+    Query query = new Query(Criteria.where("ownerEmail").is(company.getOwnerEmail()));
+    Update update = new Update();
+    ArrayList<Long> a = company.getMemberIds();
+    a.remove(memberId);
+    update.set("memberIds", a);
+
+    mongoTemplate.updateFirst(query, update, Company.class);
   }
 
   private Company getCompanyWithToken(String token) throws IllegalArgumentException {
diff --git a/src/main/java/com/MeetMate/user/User.java b/src/main/java/com/MeetMate/user/User.java
index f583b4d..00ffd32 100644
--- a/src/main/java/com/MeetMate/user/User.java
+++ b/src/main/java/com/MeetMate/user/User.java
@@ -40,7 +40,6 @@ public User(Long id, String name, String email, String password) {
     this.email = email;
     this.password = password;
     this.createdAt = LocalDate.now();
-    subscribedCompanies = new ArrayList<>();
   }
 
   @Experimentational
@@ -55,6 +54,7 @@ public User(String name, String email, String password, UserRole role) {
     this.password = password;
     this.createdAt = LocalDate.now();
     this.role = role;
+    subscribedCompanies = new ArrayList<>();
   }
 
   public Map<String, Object> generateMap() {
diff --git a/src/main/java/com/MeetMate/user/UserService.java b/src/main/java/com/MeetMate/user/UserService.java
index 3eb1d84..9a5c8bc 100644
--- a/src/main/java/com/MeetMate/user/UserService.java
+++ b/src/main/java/com/MeetMate/user/UserService.java
@@ -1,5 +1,6 @@
 package com.MeetMate.user;
 
+import com.MeetMate.company.CompanyRepository;
 import com.MeetMate.enums.UserRole;
 import com.MeetMate.response.AuthenticationResponse;
 import com.MeetMate.response.GetResponse;
@@ -16,6 +17,7 @@
 import org.springframework.util.MultiValueMap;
 
 import javax.naming.NameAlreadyBoundException;
+import java.util.ArrayList;
 import java.util.List;
 
 @Service
@@ -26,6 +28,7 @@ public class UserService {
   private final JwtService jwtService;
   private final PasswordEncoder passwordEncoder;
   private final AuthenticationManager authenticationManager;
+  private final CompanyRepository companyRepository;
 
   public GetResponse getUser(String token) {
     String email = jwtService.extractUserEmail(token);
@@ -176,6 +179,13 @@ public void subscribeToCompany(String token, long companyId) {
     if (user.getRole() != UserRole.CLIENT)
       throw new IllegalArgumentException("Only CLIENT users can subscribe to companies");
 
-    user.getSubscribedCompanies().add(companyId);
+    if(user.getSubscribedCompanies().contains(companyId))
+      throw new IllegalArgumentException("User is already subscribed to this company!");
+
+    user.getSubscribedCompanies()
+        .add(companyRepository.findCompanyById(companyId)
+        .orElseThrow(() -> new EntityNotFoundException("Company could not be found!"))
+        .getId()
+    );
   }
 }