External Storage error


I use Nextcloud 21.0.2 on Ubuntu 20.04
I have activated the external storage app and it was working but, now, I can not acces the setting page
if I click in the administration panel on the external storage entry, there is this error message

“Internal Server Error
The server is unable to perform your request.
If this happens again, please send the technical details below to the server administrator.
The server log file can provide more information.”

I don’t know how to fix the problem.

Thank you in advance for your help

I had experience the same and could fix it only by deactivating this app via occ command