The health code can't be used, which may be caused by the mobile phone network. This may happen if the mobile phone has a poor network speed or no network connection. Users are advised to check the network connection status of the mobile phone or disconnect the mobile phone network connection.
Different provinces have different risk levels, response levels and prevention and control requirements. Secondly, the standards for generating health codes vary from place to place. The health code can only prove the patient's condition at that time, and the subsequent health status cannot be simply judged accordingly. At the national level, the risk data service of epidemic prevention and control in COVID-19 is carried out nationwide, and all provinces and departments can call and query the unified database of confirmed and suspected cases, close contacts database and county-level risk grade database, basically realizing mutual recognition of basic data.