Fatal error: Uncaught Error: Class "Symfony\Contracts\EventDispatcher\Event" not found in /opt/lampp/htdocs/myhospitalnow/mhn-notifications-ms/vendor/symfony/mailer/Event/SentMessageEvent.php:20 Stack trace: #0 {main} thrown in /opt/lampp/htdocs/myhospitalnow/mhn-notifications-ms/vendor/symfony/mailer/Event/SentMessageEvent.php on line 20