If you see an error when trying to pay by card, first check that you have entered all required details correctly.
1. Details you must enter
Make sure you have entered:
The long card number
The expiry date
The security code (CVC)
A valid email address
Each of these must be in the correct field with no missing or extra digits.
2. Details you do not need to enter
You do not need to enter the name on the card.
If all required details are correct and you still see an error, you may need to try a different card or contact your card provider.