DDB App/Google Play Store Payment Processing Error

I've been having an ongoing issue with the D&D Beyond app on the Google Play Store whenever I try to purchase a membership. Every time I attempt to buy one, I get an error saying, "We could not process your payment at the moment. Please contact our support." So I click the support option, explain what's happening, and end up getting emails back from D&D Beyond support that just direct me to troubleshooting threads I've already tried and that haven't helped at all. I've also contacted Google Play support, and they told me the issue isn't on their end. So now I'm stuck going back and forth between both companies, with neither one actually helping me fix the problem. What's even more frustrating is that Google Play still takes my payment when I try to purchase the membership, then tells me I have three days to log into the app and verify the purchase before they refund me. I've gone through this multiple times now, and it's getting ridiculous. I know I could just purchase the membership through the D&D Beyond website, but I have Google Play credits specifically set aside for this, and I'd like to actually use them. I'm just trying to pay for a membership, and somehow that's turned into this whole ordeal where nobody seems to know how to help me.