Yes, it must be a credit card, that is, a credit card. For non-credit cards, there is no back italics to display the three-digit or four-digit verification code at the top of the signature on the back of the card. When purchasing with Ctrip (Group Immediately), it is difficult to enter the verification code (CVV2/CVC2). Neither the quasi-credit card nor the debit card works because there is no three- or four-digit verification code displayed at the end of the signature on the back of the card. The reason for such problems may be that Ctrip did not select non-credit card users. It is probably because credit card users generally have good credit and have medium or high incomes.