Fatal error: Uncaught Error: Class "Sabre\DAVACL\AbstractPrincipalCollection" not found in /var/www/cal.digio.space/vendor/sabre/dav/lib/CardDAV/AddressBookRoot.php:18 Stack trace: #0 {main} thrown in /var/www/cal.digio.space/vendor/sabre/dav/lib/CardDAV/AddressBookRoot.php on line 18