Fatal error: Uncaught Error: Class 'Symfony\Component\HttpKernel\EventListener\AbstractSessionListener' not found in /mnt/volume_lon1_01/backend/admin/vendor/symfony/http-kernel/EventListener/SessionListener.php:29
Stack trace:
#0 {main}
thrown in /mnt/volume_lon1_01/backend/admin/vendor/symfony/http-kernel/EventListener/SessionListener.php on line 29