I have been using a couple of expired cards in my dev kit for many weeks now. However, suddenly, since the last 2 days, my transactions have been failing. It has nothing to do with my application because the card transactions are failing on SaleApp as well as register app. Is there anything going on with the sandbox that would cause these transactions to start failing. I know these used to work because I have long history if successful transactions in the transactions app with these very same cards that are failing now.
Any insight would be appreciated.
