Google once (falsely?) considered my Revolut debit card a pre-paid card and refused to accept it for GCS billing. The error message wasn't anything generic either - it stated specifically that pre-paid cards are not accepted.
Aren't Revolut's cards prepaid? I was under the impression it's not full, real bank account since they make it easy to transfer money in out. I imagine they're making money off the issuing bank part of the interchange fees