diff --git a/packages/twenty-server/src/engine/core-modules/graphql/hooks/use-graphql-error-handler.hook.ts b/packages/twenty-server/src/engine/core-modules/graphql/hooks/use-graphql-error-handler.hook.ts
index 3f181f418..4bdc9860d 100644
--- a/packages/twenty-server/src/engine/core-modules/graphql/hooks/use-graphql-error-handler.hook.ts
+++ b/packages/twenty-server/src/engine/core-modules/graphql/hooks/use-graphql-error-handler.hook.ts
@@ -10,7 +10,10 @@ import { GraphQLContext } from 'src/engine/api/graphql/graphql-config/interfaces
 
 import { ExceptionHandlerService } from 'src/engine/core-modules/exception-handler/exception-handler.service';
 import { generateGraphQLErrorFromError } from 'src/engine/core-modules/graphql/utils/generate-graphql-error-from-error.util';
-import { BaseGraphQLError } from 'src/engine/core-modules/graphql/utils/graphql-errors.util';
+import {
+  BaseGraphQLError,
+  convertGraphQLErrorToBaseGraphQLError,
+} from 'src/engine/core-modules/graphql/utils/graphql-errors.util';
 import { shouldCaptureException } from 'src/engine/utils/global-exception-handler.util';
 
 const DEFAULT_EVENT_ID_KEY = 'exceptionEventId';
@@ -81,13 +84,29 @@ export const useGraphQLErrorHandlerHook = <
               return;
             }
 
-            // Step 1: Flatten errors - extract original errors when available
-            const originalErrors = result.errors.map((error) => {
-              return error.originalError || error;
+            // Step 1: Process errors - extract original errors and convert to BaseGraphQLError
+            const processedErrors = result.errors.map((error) => {
+              const originalError = error.originalError || error;
+
+              if (error.extensions && originalError !== error) {
+                originalError.extensions = {
+                  ...error.extensions,
+                  ...(originalError.extensions || {}),
+                };
+              }
+
+              if (
+                originalError instanceof GraphQLError &&
+                !(originalError instanceof BaseGraphQLError)
+              ) {
+                return convertGraphQLErrorToBaseGraphQLError(originalError);
+              }
+
+              return originalError;
             });
 
             // Step 2: Send errors to monitoring service (with stack traces)
-            const errorsToCapture = originalErrors.filter(
+            const errorsToCapture = processedErrors.filter(
               shouldCaptureException,
             );
 
@@ -107,15 +126,15 @@ export const useGraphQLErrorHandlerHook = <
 
               errorsToCapture.forEach((_, i) => {
                 if (eventIds?.[i] && eventIdKey !== null) {
-                  originalErrors[
-                    originalErrors.indexOf(errorsToCapture[i])
+                  processedErrors[
+                    processedErrors.indexOf(errorsToCapture[i])
                   ].eventId = eventIds[i];
                 }
               });
             }
 
             // Step 3: Transform errors for GraphQL response (clean GraphQL errors)
-            const transformedErrors = originalErrors.map((error) => {
+            const transformedErrors = processedErrors.map((error) => {
               const graphqlError =
                 error instanceof BaseGraphQLError
                   ? error
diff --git a/packages/twenty-server/src/engine/core-modules/graphql/utils/graphql-errors.util.ts b/packages/twenty-server/src/engine/core-modules/graphql/utils/graphql-errors.util.ts
index 72c080ee5..8a4afa07c 100644
--- a/packages/twenty-server/src/engine/core-modules/graphql/utils/graphql-errors.util.ts
+++ b/packages/twenty-server/src/engine/core-modules/graphql/utils/graphql-errors.util.ts
@@ -196,3 +196,51 @@ export class InternalServerError extends BaseGraphQLError {
     Object.defineProperty(this, 'name', { value: 'InternalServerError' });
   }
 }
+
+/**
+ * Converts a GraphQLError to a BaseGraphQLError with the appropriate ErrorCode
+ * based on HTTP status code if present in extensions.
+ */
+export const convertGraphQLErrorToBaseGraphQLError = (
+  error: GraphQLError,
+): BaseGraphQLError => {
+  const httpStatus = error.extensions?.http?.status;
+  let errorCode = ErrorCode.INTERNAL_SERVER_ERROR;
+
+  if (httpStatus && typeof httpStatus === 'number') {
+    switch (httpStatus) {
+      case 400:
+        errorCode = ErrorCode.BAD_USER_INPUT;
+        break;
+      case 401:
+        errorCode = ErrorCode.UNAUTHENTICATED;
+        break;
+      case 403:
+        errorCode = ErrorCode.FORBIDDEN;
+        break;
+      case 404:
+        errorCode = ErrorCode.NOT_FOUND;
+        break;
+      case 405:
+        errorCode = ErrorCode.METHOD_NOT_ALLOWED;
+        break;
+      case 408:
+      case 504:
+        errorCode = ErrorCode.TIMEOUT;
+        break;
+      case 409:
+        errorCode = ErrorCode.CONFLICT;
+        break;
+      default:
+        if (httpStatus >= 400 && httpStatus < 500) {
+          // Other 4xx errors
+          errorCode = ErrorCode.BAD_USER_INPUT;
+        } else {
+          // 5xx errors default to internal server error
+          errorCode = ErrorCode.INTERNAL_SERVER_ERROR;
+        }
+    }
+  }
+
+  return new BaseGraphQLError(error.message, errorCode, error.extensions);
+};