Social security will be deducted one month in advance.

Your question is not very clear. I will give you an answer in two situations:

Social insurance is generally deducted from the bank. If the deduction is unsuccessful due to insufficient balance, the social security center will notify you by SMS. Generally, you can pay by cheque or credit card directly before next month 15. After 15 and before 19, you can only pay by credit card. There will be no late payment fee. This is the first case.

In the second case, if you haven't paid it after 19, then before the 25th (the time of each bank is slightly different), you will deposit a certain amount in the bank, and the bank will automatically deduct the arrears, and there will be no late payment fee.

So, you should understand.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.