When the credit card holder is not the same as a passenger or when the security system Viva.gr indicates dangerous values for transactions then you will be asked to send a fax or email with a photo of the credit card that used and the passport of the card holder and passengers. Note that Viva.gr reserves the right to cancel a transaction if it has elements that make it suspicious and dangerous in terms of security. If this happens you should contact us for your credit card refund.