duplicate to staff below/above not working

I attach a file where these actions don’t seem to work. I have cut down the original file to a few bars in order to test it here.
When I select a bar and use the duplicate commands nothing seems to happen.
Copy problem.dorico.zip (580 KB)

I think the issue here is that once upon a time each of the instruments in this project had two staves, and it no longer does, so it’s duplicating onto the staff that you have since deleted. For the time being, I suggest you add four new players with fresh instruments and copy and paste the material from these staves onto the four new staves, and you should find everything then works more as you would expect.

If I understand correctly then theses commands don’t work when there are divisi involved?

At the moment, no, because the copy and paste commands aren’t always handling the additional staves correctly under all circumstances.