17.0.03 "Die Aktualisierung ist noch nicht abgeschlossen"

Dear community,

I run mentioned nextcloud version and I want to let the updater change to version 18.0.4. Mentioned sentence occurs in the overview. I searched the community on solutions. There were hints such as changing the name of the updater folder but unfortunately this did not work. Does anybody can help? Maybe problem is already known. Thanks a lot, Equardo