@Rich5000 Are you mining through the windows App right?
When you click on mining it pop ups a message where you choose the pool you are getting in, there you have on the left side two buttons, one say change reward assignment and the other it's the same but to use when you get some error and it says there... try to do with that button should work... I gotta run pal, but i will help you when i come back in a few hours if this is not resolved yet...