When buying mooncakes on Tmall, some merchants will give mooncake cards to promote sales and give back to customers. The moon cake card is a kind of exchange method. After receiving the mooncake card, you can redeem it according to the above tips. Enter the password on the mooncake card and enter the designated page to get the corresponding mooncake. This is a common way to promote sales, that is, to attract consumers to buy moon cakes and provide additional benefits.