External storage: You don't have permission to upload or create files here

Hi! I have Nextcloud snap installed on Ubuntu 18.04. I’ve mounted external storage as per the snap instructions, in:
/media/shares.
and then downloaded the external storage app in Nextcloud and added to folders, /media/shares/Photos and /media/shares/Documents.

I have scanned the folders with
/snap/bin/nextcloud.occ files:scan --all
and that worked fine. I’ve also generated previews for all photos with
/snap/bin/nextcloud.occ preview:pre-generate

The problem is that I can only access Photos, not Documents. Why is that?

Any help would be appreciated!

Is was the permissions for the external storage folders that was the issue. Changing those (in unRAID in my case) was the solution.