Fatal error: Uncaught Error: Class 'Symfony\Contracts\EventDispatcher\Event' not found in C:\xampp7\htdocs\sigpkl\vendor\symfony\event-dispatcher\GenericEvent.php:26 Stack trace: #0 {main} thrown in C:\xampp7\htdocs\sigpkl\vendor\symfony\event-dispatcher\GenericEvent.php on line 26