I strongly suggest that you have a look at your bill. You are not clear about the credit line, billing period, billing date, repayment date and other concepts, and your operation or understanding is also wrong.

1. The billing date is A, that is, the period from A+1 of last month to A of this month is B, and the total amount of consumption and cash withdrawal is D;

2. If the repayment date is C, then the cash withdrawal amount D incurred in account period B should be paid off before C of next month;

3. There are three credit lines for a credit card:

Credit line: refers to the maximum amount that the bank can grant you to spend by credit card;

available line: refers to the maximum amount that the bank grants you to spend by credit card minus the amount that you have spent in the accounting period and the amount that you may owe before (that is, the maximum amount that the bank grants you to spend by credit card minus the money that you owe to the bank, including your consumption, cash withdrawal, and some related expenses, such as cash withdrawal fee, interest, annual credit card fee, etc., if any). This line is usually lower than the credit line, in some cases. In the case of repayment, your available line will gradually return to be consistent with the credit line.

advance cash limit: usually it is half of the credit limit (each bank may have different requirements, and China Merchants Bank has half).

4. According to the analysis you described, you should not have clearly expressed the real situation of your card use process, so I suggest you clarify the above three questions I said. It is possible that your initial credit limit is not 3;

5. The bank won't give you an increase in the credit line without informing you. Don't dream like that. Besides, if the bank increases the credit line without your consent, it will bear additional risks.