Big problem with files&folder locking feature

Hello,

i had created a folder (with lots of subfolders and lots of files in every subfolder) and then i shared the main folder to a group (4 users of my nextcloud are associated to that group). I gave only the right to share (no create, no change, no delete -right)

The big problem is:
Any of the 4 users of the group is able to lock this shared folder thus also the admin (me) has no access to that shared folder (and all subfolders/files). The shared folder is now also locked for the admin (and all other users).
And any of the users of the group can rename and delete the shared folder. I tried to use a group-folder instead, but with group-folders it is not possible to give the users of the group only some special rights like only sharing but no creating/changing/deleting.

How can that problem be solved.

Does it make sense to allow read-only users to lock files? I’d open a bug report on github.com/nextcloud/server/issues