Not able to delete one file

Dear everybody,
I have a problem with one file, which I cannot delete. In the logfile is this entry:

Exception: {“Message”:“HTTP/1.1 423 “FOLDERYYY\FILE.YYY” is locked”,“Exception”:“OCA\DAV\Connector\Sabre\Exception\FileLocked”,"…

I already tried this:

But maybe I did it wrong?!?!

I installed my Nextcloud setup with this tutorial with Redis-Server:

I hope someone can help me :smiley:

Sorry, the solution did worked, it just takes some time…