All files in the sync folder ” folder were deleted on the server

I have a directory that is shared with a collegue. Although no sync issues, there are a number of directories that I have within the shared folder that contains files, that he does not have. He has the directory but it is empty. If I do a show hidden files then I can see a lot of empty files with a . like (.filename.ext)

To try and rectify this, I unticked a directory from his sync on his nextcloud, clicked apply and then ticked it again and applied, which then resynced that directory and the files came back.

I then unticked all of the directories on his nextcloud client > apply but then got a message saying:

"All files in the sync folder Clients folder were deleted on the server with an option to “Keep files” or “Remove all files” - Surely this cannot be correct or am I missing something? I dont want to delete ANY files, I simply want to get the sync working, and I cannot see how his unsync would actually delete files ON THE SERVER which I shared with him?

Please can someone explain this to me?

i have the same problem.
same way and same effect.