Wrong Google Play account popping up for in game purchases

I found the solution a while back but cannot find it again (new phone). My SWGOH account is [edit: email address removed]. I have a Google Rewards account with [edit: email address removed].

When I try to make an in-game purchase, it pulls up the play account for [edit: email address removed] (and then I cannot use my Google Rewards points).

The solution had to do with logging out and back in of accounts in multiple places. Help?