Fatal error: Uncaught Error: Interface "Ratchet\WebSocket\WsServerInterface" not found in C:\xampp\htdocs\hannoole\schol\vendor\cboden\ratchet\src\Ratchet\Wamp\TopicManager.php:6 Stack trace: #0 {main} thrown in C:\xampp\htdocs\hannoole\schol\vendor\cboden\ratchet\src\Ratchet\Wamp\TopicManager.php on line 6