Btw I think people already know this but just for information. Don't use billdesk QR to pay from Amazon (or another) Wallet instead do a bank transfer to the credit card account (check bank website for CC IFSC info), for eg AMEX provides both bank transfer and UPI for CC payment, AEBC<15-digit-card-no>@SC. It's quick, and you immediately receive the bank payment confirmation SMS.