Fatal error: Uncaught Error: Interface "Sabre\Xml\XmlSerializable" not found in D:\xampp\htdocs\pimcore\my-project\vendor\sabre\dav\lib\CalDAV\Xml\Property\Invite.php:26 Stack trace: #0 {main} thrown in D:\xampp\htdocs\pimcore\my-project\vendor\sabre\dav\lib\CalDAV\Xml\Property\Invite.php on line 26