The authoritative explanation of Bank of Communications Card Department: Look at the bill clearly! Is your credit card only in installments and there is no other consumption? If so, you can return it to 600 yuan as you say, and then you don't have to return it next month, and then you can return it in the third month! (the premise is that you can't use credit cards anymore! Otherwise, the money you saved will be deducted from the money you spent first, so you can't repay your pre-existing 300 yuan after the next installment. The credit card installment fee is quite high. I suggest not to do it again!

Friendly reminder: since I have not seen your bill information with my own eyes, all the bills issued on the bill sheet shall prevail! Bank of Communications has worry-free card, credit guarantee, credit guarantee and other charging services! Confirm whether it is open or not, because the charge will be deducted from the credit card. I don't know some charging items of China Everbright Bank. You can ask questions