Temporary files of a word file (like **~$wordfilename.docx**) aren't deleted after closing main file

MacOs Client - 9.0.4
Server on Ubuntu 20 - 10.0.1

Client on other computer creates hidden temporary files of a word file (like ~$wordfilename.docx) file but then doesn’t delete the temporary file after the main file got closed.

So the actual main word file doesn’t get synced but is locked.

Sync Temporary files of MS Office is DISABLED on my client.

Does anyone know if this is a known issue?

Greetings, Chris