diff --git a/CHANGELOG b/CHANGELOG
index aee70445e52..dc749a529d1 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -101,6 +101,7 @@
 * Decidir and DecicirPlus: Add the wallet_id field [yunnydang] #5354
 * Worldpay: Update where to pass shopperIPAddress [almalee24] #5348
 * Braintree: Account for BraintreeError [almalee24] #5346
+* Worldpay: Fix stored credentials unscheduled reason type [Buitragox] #5352 
 
 == Version 1.137.0 (August 2, 2024)
 * Unlock dependency on `rexml` to allow fixing a CVE (#5181).
diff --git a/lib/active_merchant/billing/gateways/worldpay.rb b/lib/active_merchant/billing/gateways/worldpay.rb
index 495aead6d37..47b958f1090 100644
--- a/lib/active_merchant/billing/gateways/worldpay.rb
+++ b/lib/active_merchant/billing/gateways/worldpay.rb
@@ -1169,7 +1169,6 @@ def generate_stored_credential_params(is_initial_transaction, reason = nil, init
         stored_credential_params = {}
         stored_credential_params['usage'] = is_initial_transaction ? 'FIRST' : 'USED'
 
-        return stored_credential_params unless %w(RECURRING INSTALMENT).include?(reason)
         return stored_credential_params if customer_or_merchant == 'customerInitiatedReason' && stored_credential_params['usage'] == 'USED'
 
         stored_credential_params[customer_or_merchant] = reason if reason
diff --git a/test/unit/gateways/worldpay_test.rb b/test/unit/gateways/worldpay_test.rb
index 9b49ae02b67..d0e500b704c 100644
--- a/test/unit/gateways/worldpay_test.rb
+++ b/test/unit/gateways/worldpay_test.rb
@@ -422,7 +422,7 @@ def test_authorize_passes_stored_credential_options
     response = stub_comms do
       @gateway.authorize(@amount, @credit_card, options)
     end.check_request do |_endpoint, data, _headers|
-      assert_match(/<storedCredentials usage\=\"USED\"\>/, data)
+      assert_match(/<storedCredentials usage\=\"USED\" merchantInitiatedReason\=\"UNSCHEDULED\"\>/, data)
       assert_match(/<schemeTransactionIdentifier\>000000000000020005060720116005060\<\/schemeTransactionIdentifier\>/, data)
     end.respond_with(successful_authorize_response)
     assert_success response
@@ -437,7 +437,7 @@ def test_authorize_with_nt_passes_stored_credential_options
     response = stub_comms do
       @gateway.authorize(@amount, @nt_credit_card, options)
     end.check_request do |_endpoint, data, _headers|
-      assert_match(/<storedCredentials usage\=\"USED\"\>/, data)
+      assert_match(/<storedCredentials usage\=\"USED\" merchantInitiatedReason\=\"UNSCHEDULED\"\>/, data)
       assert_match(/<schemeTransactionIdentifier\>000000000000020005060720116005060\<\/schemeTransactionIdentifier\>/, data)
     end.respond_with(successful_authorize_response)
     assert_success response
@@ -448,7 +448,7 @@ def test_authorize_with_nt_passes_standard_stored_credential_options
     response = stub_comms do
       @gateway.authorize(@amount, @nt_credit_card, @options.merge({ stored_credential: stored_credential_params }))
     end.check_request do |_endpoint, data, _headers|
-      assert_match(/<storedCredentials usage\=\"USED\"\>/, data)
+      assert_match(/<storedCredentials usage\=\"USED\" merchantInitiatedReason\=\"UNSCHEDULED\"\>/, data)
       assert_match(/<schemeTransactionIdentifier\>20005060720116005060\<\/schemeTransactionIdentifier\>/, data)
     end.respond_with(successful_authorize_response)
     assert_success response
@@ -495,6 +495,19 @@ def test_authorize_passes_correct_stored_credentials_for_first_installment
     assert_success response
   end
 
+  def test_authorize_passes_correct_stored_credentials_for_first_unscheduled
+    options = @options.merge(
+      stored_credential_usage: 'FIRST',
+      stored_credential_initiated_reason: 'UNSCHEDULED'
+    )
+    response = stub_comms do
+      @gateway.authorize(@amount, @credit_card, options)
+    end.check_request do |_endpoint, data, _headers|
+      assert_match(/<storedCredentials usage="FIRST" merchantInitiatedReason="UNSCHEDULED">/, data)
+    end.respond_with(successful_authorize_response)
+    assert_success response
+  end
+
   def test_authorize_passes_sub_merchant_data
     options = @options.merge(@sub_merchant_options)
     response = stub_comms do
@@ -1715,10 +1728,28 @@ def test_authorize_prefers_options_for_ntid
     assert_success response
   end
 
+  def test_authorize_stored_credentials_for_initial_customer_transaction
+    options = @options.merge!(
+      {
+        stored_credential: {
+          initial_transaction: true,
+          reason_type: 'unscheduled',
+          initiator: 'cardholder'
+        }
+      }
+    )
+
+    response = stub_comms do
+      @gateway.authorize(@amount, @credit_card, options)
+    end.check_request do |_endpoint, data, _headers|
+      assert_match(/<storedCredentials usage\=\"FIRST\" customerInitiatedReason\=\"UNSCHEDULED\"\>/, data)
+    end.respond_with(successful_authorize_response)
+    assert_success response
+  end
+
   def test_authorize_stored_credentials_for_subsequent_customer_transaction
     options = @options.merge!({
       stored_credential: {
-        network_transaction_id: '3812908490218390214124',
         initial_transaction: false,
         reason_type: 'recurring',
         initiator: 'cardholder'
@@ -1729,7 +1760,6 @@ def test_authorize_stored_credentials_for_subsequent_customer_transaction
       @gateway.authorize(@amount, @credit_card, options)
     end.check_request do |_endpoint, data, _headers|
       assert_match(/<storedCredentials usage\=\"USED\"\>/, data)
-      assert_not_match(/<schemeTransactionIdentifier\>000000000000020005060720116005060\<\/schemeTransactionIdentifier\>/, data)
     end.respond_with(successful_authorize_response)
     assert_success response
   end