Fatal error: Uncaught Error: Interface 'Psr\EventDispatcher\EventDispatcherInterface' not found in /opt/lampp/htdocs/vendor/symfony/event-dispatcher-contracts/EventDispatcherInterface.php:19 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/vendor/symfony/event-dispatcher-contracts/EventDispatcherInterface.php on line 19