Qatar Airways takes payment security seriously. In order to ensure that the use of your payment card was authorised, we ask you to give us additional information, such as card statements showing the payment for the ticket. This allows us to verify that the cardholder approved the transaction to purchase the ticket. Especially in cases where the passenger is different from the cardholder, we take extra precautions to ensure that the use of the payment card was authorised.
For more information on the terms & conditions of paying by credit card please visit the link below
https://www.qatarairways.com/en/legal.html ("Paying by credit card")