Leaking screw stop on shower valve

My shower head is leaking. I have a ~15 year old Danze Glacier Bay shower valve (please see picture). I assumed it needed a new cartridge. After checking out all the help here and elsewhere I felt I could try it. Mistake.

I tried to use the screw stops to turn off the water. It didn’t work. They started off turned all the way counterclockwise (as shown). I gave clockwise turns, and the cold water started coming out pretty good from the stop. It drips from where the thread inserts. I turned it all way back counterclockwise but now it has a slow leak. So I have made things worse.

What’s best thing to do next?

Any help appreciated.