I noticed another poster made a post about hosted checkout and my guess is that this may be related. I am receiving the following error when attempting to make payments on a sandbox account using the iFrame method:
402 Payment Required: card_declined: SERV NOT ALLOWED: Card type cannot be processed on your merchant processing account. Ask for another form of payment. Contact support if you believe this to be incorrect.
The sandbox MID in question is 8D1K52RWAHXPC. It appears that cards are not being accepted in general, as I've tried every test number on the test card numbers page.
I should note that production is working fine, and the last time I was able to use sandbox for this successfully was less than 30 days ago. This has been a working integration for years and I'm certain it's not a code related issue.
