> if my card was already accepted once and I successfully approved the payment via 3D secure with my bank, who are you (as a random online service) to assume yo

> if my card was already accepted once and I successfully approved the payment via 3D secure with my bank, who are you (as a random online service) to assume you can act as my big brother? Even more, if I'm using a balance paid by gift card, who give Amazon or other services the right to put my account on hold while it still contains my hard earned money[?] There are many payment methods around the world that have different rules, but for Visa, MC, and Amex cards issued by American banks, the merchant, not the card issuer, has the liability to repay fraudulent on-line purchases (so-called "card not present" transactions). The merchant is the one accepting the risk, not your bank. So they decide which transactions they will accept liability for and which they will decline and what you need to do to prove that their liability is low. In addition, some second-factor systems (like possibly 3D secure) shift the liability from the merchant to the issuer when passed, but banking rules are arcane, and it is likely that 3D secure only shifts the liability for the one transaction that triggered it, and not any subsequent transactions.