Fatal error: Uncaught Error: Interface 'JMS\Serializer\Handler\SubscribingHandlerInterface' not found in /home/itscm/dev.its.cm/itsgateway/vendor/friendsofsymfony/rest-bundle/Serializer/Normalizer/FlattenExceptionHandler.php:19 Stack trace: #0 {main} thrown in /home/itscm/dev.its.cm/itsgateway/vendor/friendsofsymfony/rest-bundle/Serializer/Normalizer/FlattenExceptionHandler.php on line 19