Fatal error: Uncaught Error: Class "Sabre\DAV\Collection" not found in C:\Apache24\htdocs\dle\engine\classes\composer\vendor\sabre\dav\lib\CalDAV\Notifications\Collection.php:25 Stack trace: #0 {main} thrown in C:\Apache24\htdocs\dle\engine\classes\composer\vendor\sabre\dav\lib\CalDAV\Notifications\Collection.php on line 25