This error indicates that the customer’s bank is unwilling to accept the transaction. It’s causes are diverse and difficult to pin down without contacting the bank, but some of the typical reasons the code is returned include an incorrect card number or expiration date entered on the checkout page, insufficient funds in the associated bank account and a rejection based on fraud filters at the bank. Being a soft decline (the result of a temporary issue), the best way to troubleshoot this error is to simply retry the card at a later time. If the error persists, consider contacting the customer with a request to try a different payment method and/or send a query to her bank.