I have been making regular payments to NS&I with my Curve for a while until a few days ago. Transactions got declined with the message “invalid card number”. I contacted NS&I and Curve, both said they did not block the transaction. I have found a couple of similar cases here before I submitted this topic:
Anyone any ideas, please?
P.S. no changes were made between the last successful payment and the first declined payment and my Curve still works for all other payments.