So to explain this next cluster....wordIcan'tuse-
Bank account A - registered to my current address, up to date card, don't know the PIN for it. I keep forgetting. Stopped bothering to ask them to send me it out, because I keep forgetting. Account's also overdrawn.
Bank account B - only exists because I'm too lazy to go to Middleton and close it. I have the PIN, I have the card, it's not contactless. It's also registered to my old address (and apparently my old phone number somehow) because ringing them up is...painful. And I always figured I'd do it after I moved, then tomorrow, then next week, and now it's been a year and I'm too embarrassed to call up.
So. I can't register Bank account B with Google Pay because, well, obvious reasons. I can register Bank account A. I'll scrounge up the cash somewhere, better than having Bank B freak out because my card's being used in London, which they will. They're good at that. Also great at locking me out of my account with no notice because somebody somewhere's in a bad mood. Tossers.