ctrl+M not working

In Libreoffice 6 on anorther PC (always witk Kubuntu) ctrl+M works (clear direct formatting), in my main PC does not work: I don’t understand why…
Not working clear direct formatting also with other key combinations, such ctrl+shift+x.
Works if called from menu.
Ctrl+M works in LibreCalc
Thank you

As other user ctrl+M in LibreWriter works. So there is something wrong in my settings…

Solved! Renaming registrymodifications.xcu.