Fatal error: Uncaught Error: Class "OCP\Migration\SimpleMigrationStep" not found in /var/www/html/nextcloud/apps/dav/lib/Migration/Version1006Date20180628111625.php:16 Stack trace: #0 {main} thrown in /var/www/html/nextcloud/apps/dav/lib/Migration/Version1006Date20180628111625.php on line 16