It could be an issue with the shop’s card machine or the ATM if your card is working elsewhere. Here are a few other things to check:
If you’re paying using contactless
Try using Chip and PIN instead and see if the payment goes through. You’ll also need to use Chip and PIN:
- when you’re using a new contactless card for the first time
- if you’re making a payment of more than £30
- every now and then as a security check.
If you’re paying using Chip and PIN
Make sure you’re putting in the right PIN. If you can’t remember it, you can get a PIN reminder.