I have a Zhang Changcheng Global Credit Card, and the black one is useless. Today, the Bank of China sent me a message asking me to repay 100. What kind of money is this?

100 yuan is basically an annual fee. If the card is activated and not used, an annual fee will be charged. You can call on the back of the card and generally promise to spend enough for one month, and you can also refund the annual fee. If you cancel when you don't use it in the future, you won't charge an annual fee.