Fatal error: Uncaught Error: Class 'Sonata\NotificationBundle\Backend\QueueBackendDispatcher' not found in /home/lafaamicps/www/symfony/vendor/sonata-project/notification-bundle/Backend/MessageManagerBackendDispatcher.php:24 Stack trace: #0 {main} thrown in /home/lafaamicps/www/symfony/vendor/sonata-project/notification-bundle/Backend/MessageManagerBackendDispatcher.php on line 24