user serializer validation bug

apps/authentication/api/v1/serializers/serializer.py

@@ -121,6 +121,8 @@ class UserSerializer(serializers.ModelSerializer):
             if self.instance.national_code != national_code:
                 if self.Meta.model.objects.filter(national_code=national_code).exists():
                     raise UserExistException()
+        
+        return attrs
 
     def to_representation(self, instance):
         """ Custom output """