Wherever you go, you need to use the health code of that area. For example, to go to Guangdong, you need to show the health code of Guangdong. So if you want to go back to Xuzhou, you need to show your health code in Xuzhou.
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How to switch the use of Xuzhou health code;
1 Open Alipay on the mobile desktop.
2 Click "Health Code".
Click "Select Region-Beijing".
4 After switching to Xuzhou, click "View Now".
5 Click "Add Family Members".
Click to display his or her "Health Code".
The system will automatically display his or her health code and show it to the inspector.