Chord symbols where I don't want them

Hello, I am doing an ordinary piano-vocal piece (sometimes called the Grand Staff). I would like chord symbols to appear above the vocal part but not also above the r.h. of the piano, but only when the vocalist is singing. When not singing, I then want the chord symbols above the r.h. of the piano since the vocal staff (staves) will be hidden to cut down on the number of pages.

When I delete a symbol above the r.h., all symbols are deleted, even the ones I want.

I know how to turn off chord symbols in the Set Up panel. I also know how to create a Chord Symbol Region. My problem seems to be whatever Default setting I need to overcome.

Suggestions welcome, as always, thanks in advance.

Have you tried this yet?

That was the setting I sought, thanks.