1. There may be a problem with the system or network. You can wait for a while, or try another mobile phone network.
2. It may be because the health code is invalid, so it cannot be scanned.
3. Health code is a personal two-dimensional code based on actual real data, which is generated by citizens or people returning to work through self-service online declaration and background audit. As an individual entering and leaving electronic certificate locally, the QR code can be declared once, which is universal in the whole city. The introduction of the health code aims to make the work of returning to work more accurate, scientific and orderly.