Troubleshooting Orders
How to handle a ‘Payment failed’ order status 
In stores that use online payment, a problem with the payment transaction can cause a new order to be given the 'Payment failed' status. This status is indicated by a card with a red triangle in the Order List.
It is recommended to cancel an order which has the 'Payment failed' status. A window will appear in which you can specify the reason for the order cancellation. This message is mailed back to the shopper to inform him or her why the order will not be processed. By explicitly letting the shopper know that the order failed, you avoid possible misunderstandings: the shopper may not be aware that the payment was not processed and waits for an order that never arrives. If you cancel the order, the shopper can take the initiative to place a new order.
 
doc. version 6.0.4