Fatal error: Uncaught Error: Class "Sabre\DAVACL\AbstractPrincipalCollection" not found in /home/byteshos/public_html/hrm.byteshosting.net/vendor/sabre/dav/lib/Sabre/CardDAV/AddressBookRoot.php:16 Stack trace: #0 {main} thrown in /home/byteshos/public_html/hrm.byteshosting.net/vendor/sabre/dav/lib/Sabre/CardDAV/AddressBookRoot.php on line 16