The reasons why there will be overdraft interest payments on credit card No. 1 are:

1. It may be the remaining cash withdrawal interest from the previous bill.

2. Directly using the credit card limit to purchase foreign exchange to repay U.S. dollar debts is also regarded as an overdraft withdrawal. Credit card overdraft interest is generally calculated based on 5% of the minimum repayment amount, so you must use credit cards rationally and understand the problems with credit cards to save extra fees.