Fatal error: Uncaught Error: Interface "Sabre\Xml\Element" not found in /var/www/illumine/vendor/sabre/dav/lib/DAV/Xml/Element/Sharee.php:21 Stack trace: #0 {main} thrown in /var/www/illumine/vendor/sabre/dav/lib/DAV/Xml/Element/Sharee.php on line 21