Points reset when logging in
I started to use the app without logging in. I earned some points. When I went to redeem them I was told I needed to enter an email address. I couldn't find a way to do that, but I did log in with my usual Yahoo account. When I did that, my points reset to zero.
I think any points should be retained when somebody logs in, or at least when the account the person is logging into hasn't yet earned points in the app.