This error occurs when a different billing address is given to the one the payment card is registered to. Please ensure that your billing address directly matches the address where your card is registered – check for rogue spaces
The payment may show in your pending transactions for a few days but will then return into your account as the payment was blocked.
Are you sending the order to a different delivery address? If so, un-check the tick box on the checkout page and enter in your billing address there.
If you continue to experience problems, please raise a support ticket with us HERE.