Personal doorbell code will not expire as long as it is collected for the first time and is not repeated.
Doorbell code is set to better prevent and control, and strictly check the flow of people and travel routes of shopping malls and merchants. Merchants need to apply with the industrial and commercial registration number, and then customers need to download Linxi to scan when they enter the mall or shop. All personal travel codes, health codes, nucleic acid test results and vaccination information will be displayed. Conducive to prevention and control work.