Fatal error: Uncaught Error: Class "Symfony\Contracts\EventDispatcher\Event" not found in /home/www/aes-demo/api-8.0.0#316/vendor/symfony/event-dispatcher/GenericEvent.php:26 Stack trace: #0 {main} thrown in /home/www/aes-demo/api-8.0.0#316/vendor/symfony/event-dispatcher/GenericEvent.php on line 26