Hello, if you mean the reserved information for logging in to personal online banking, "reserved information" is a measure taken by China Postal Savings Bank to help you effectively identify bank websites and prevent criminals from using fake bank websites for fraud; When you log in to the online bank, the Postal Savings Bank will display your reserved information on the page, so that you can verify whether it is a real personal online bank of the Postal Savings Bank.

I hope my answer is helpful to you.