Debit card balance is negative, usually because part of your funds are in current account and part of your funds are in Qian Shengqian account (interest income is higher than current account). When the expenditure exceeds the current balance of the day, the funds in Qian Shengqian will be overdrawn automatically, and the current balance of the day will be shown as negative. At the end of the day, Qian Shengqian funds will cover the current account, and the current balance will be displayed as zero.