Can’t delete BANK from Apple Credit Card

I switched banks, so I added my new bank as a source of payment for my Apple Mastercard. When I tried to delete the old bank, I got this message:

Could Not Delete

Bank Account

Payments related to this bank account exist. Please delete them first.

I owe nothing more on the card and my Apple Pay is linked only to my new bank account.

I saw my question in this forum elsewhere, but it was answered as if the CARD was to be removed—so not helpful.

Any suggestions?