That's an overpayment. For example, it should have been returned to 800 yuan. If 900 yuan has been paid back, it will become-100 yuan. \ x0d \ x0d \ credit card balance, that is, the generated consumption limit. \x0d\ For example, if the available amount is 10000 yuan and 1000 yuan is spent, then this 1000 yuan is the balance, and the remaining 9000 yuan is the available amount. \x0d\ deposit 1000 yuan, balance is-1000 yuan, available line is 1 1000 yuan. \x0d\\x0d\ Therefore, when the balance is positive, it needs to be repaid; When it is negative, it means that there is overpayment and there is no need to repay.