Fatal error: Uncaught Error: Interface "Sabre\DAV\Auth\Backend\BackendInterface" not found in /home/tzuovhm/tzuovhm/3rdparty_/sabre/dav/lib/DAV/Auth/Backend/AbstractBearer.php:24 Stack trace: #0 {main} thrown in /home/tzuovhm/tzuovhm/3rdparty_/sabre/dav/lib/DAV/Auth/Backend/AbstractBearer.php on line 24