Fatal error: Uncaught Error: Interface "JMS\Serializer\Handler\SubscribingHandlerInterface" not found in /home/activeexcavators/public_html/vendor/jms/serializer/src/Handler/FormErrorHandler.php:18 Stack trace: #0 {main} thrown in /home/activeexcavators/public_html/vendor/jms/serializer/src/Handler/FormErrorHandler.php on line 18