it's not using the email I use to log in, or the email I have Google play set up (same address actually)
You can try removing all accounts from your phone, and login first and only your main one.
I had the same problem. Uninstalling and reinstalling Ingress fixed it for me.
I've fixed this before by uninstalling ingress and reinstalling it while making sure I am signed into the playstore with the account I want to be using for payments