How often can Nanchang Changtong code be printed?

Nanchang unblocked code can be printed for 7 days at a time. According to the relevant public information, the printed paper health code certificate is valid for 7 days, and the latest health code can be saved for printing after expiration. Health codes are based on actual data and can be generated by citizens or people who have returned to work through 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.