Originally Posted by craigthemif

IIRC Marriott doesn't pause to do the card verification process (App, text message, whatever) on points purchases.

I would suspect that the OP's cards are set up to require verification which Marriott doesn't do. Thereby allowing Marriott and the banks to blame each other...

Sometimes you can get around this with fintech apps that issue a single-use credit card number for online spending...