the late payment fee is charged at 5% of the unpaid part of the minimum repayment. You owe more than 3,7 yuan in the previous period, and the minimum repayment is expected to be around 311.2 (the specific figure is subject to the bill), so the late payment fee is around 311.2*5%=15.66, which is basically consistent with your 15.66, because I don't know what your minimum repayment last month was. The interest is 37* (the date when you spend 37 to the time when you repay it +5 days) * five ten thousandths. Add your credit card consumption on March 28th. Your bill date is April 1th, and the repayment period is April 3th. As a result, you didn't pay it back until May 5th. Didn't you say it was five days late, that's 37 * (May 5th-March 28th) * five ten thousandths. About the same as yours. You should understand the way he pays interest. Once you don't repay in time, you should pay interest in full, and count from the time you spend each time to your repayment time. The interest rate is still relatively high.