Fatal error: Uncaught Error: Class "Sabre\DAV\Collection" not found in /var/www/cal.digio.space/vendor/sabre/dav/lib/CardDAV/AddressBook.php:19 Stack trace: #0 {main} thrown in /var/www/cal.digio.space/vendor/sabre/dav/lib/CardDAV/AddressBook.php on line 19