1. How to use credit cards
Here we talk about general credit card fraud. The standard solution is to contact the bank and explain that a transaction was not authorized by me. The bank will immediately cancel the transaction, and then there will be a lawsuit between the bank and the merchant, and the credit card user no longer needs to be involved in anything. The bank will also decide whether to apply for a new card with a different card number for you depending on the situation. Of course, the above is a standard solution, but it is slightly different in China. To be precise, the bank does not care much about it.
Once the above information is obtained, in theory anyone can use this credit card to make purchases, so even the information printed on the card should be kept as confidential as possible. Once you add a credit card information to Amazon, you will never see your full card number on Amazon's website; only the last four digits of the card number will be displayed wherever credit card information is displayed. This ensures that even if someone logs into your account, they will not be able to obtain your complete credit card information.
Since your credit card information is saved and you don’t need to re-enter it for future purchases, if someone else logs into your Amazon account, can they use your credit card information to buy something for themselves? Still not working, the reason is that every time you want to send an order to a new address, Amazon will ask you to re-enter your credit card information. This way, even if someone hacks into your account, they won't be able to use your credit card to ship orders to their address. The setting for "one-click ordering" is similar: a one-click ordering setting contains two parts: shipping address and credit card. The intruder must either choose a saved address or re-enter the credit card information.
If someone hacks into your account and places an order for you, you need to react quickly and cancel the order before it is prepared. If unfortunately it is no longer possible to cancel the order, you can refuse it upon delivery.
For Kindle books, if you purchased them through "One-Click Ordering", you can cancel the order within half an hour and your credit card will not be charged (Amazon Help). If it takes more than half an hour, or if it was purchased through ordinary methods, you can apply for return within 7 days (Amazon Help: Kindle Return and Exchange Policy).
Of course the most important thing is to change your password immediately.