corrupt files in /export/

Hello,

when changing a setting in mergerfs I got the message that /export/Daten could not be created (as it already exists).
That's true:

ls -l /export/
ls: Zugriff auf '/export/Paperless' nicht möglich: Datei oder Verzeichnis nicht gefunden
ls: Zugriff auf '/export/Daten' nicht möglich: Datei oder Verzeichnis nicht gefunden
insgesamt 12
drwxr-xr-x 2 root root 4096 Dez  5  2017 Backupdrive
d????????? ? ?    ?       ?            ? Daten
d????????? ? ?    ?       ?            ? Paperless
drwx------ 2 root root 4096 Apr  1  2017 video
drwx------ 2 root root 4096 Jan  2  2017 Video

I cannot delete these two Folders (Daten, Paperless). So I booted the Systemrescue cd, did an (forced) fsck --> all good. No errors found.
So I deleted both folders --> no problem
I booted OMV --> again these folders were there without the possibility to delete.

I stopped nfs-kernel-server and portmap --> still the same.

Does anyone have more Ideas?

Regards,
Hendrik

I got the Idea to find the process using those Folders with lsof.
It's mergerfs.
Unmounting these lets me delete the folders.
I keep these posts for any other poor guy with this problem.