This just randomly hit me as well. Multiple good cards from different banks, all declined.
EDIT: I seem to be fixed, also randomly? I’ll put what I did below for anyone else to try.
- Waited a couple days, tried again successfully purchasing something else entirely
- Have not retried any buying of the three items that were in the stalled cart
- Successful attempt was on a windows 10 machine, previous failures were on a MBP.
- before making the paid purchase, I deliberately “bought” a free asset I did not need
- made the second paid purchase using “buy now” bypassing cart.
- suspect something had flagged my account (crappy fraud heuristics?) but it may have been related to one of the three things I tried to purchase, or the cart itself. Who knows.