Enter the self-declaration applet through the menu bar of the official account of "I Shenzhen" WeChat, click "Old and Young Health Code Inquiry" in the common area of the homepage, and authorize the inquired person to use his ID number to inquire about the health code status. Fill in the ID number of the inquired person correctly, and click Query. After the query is successful, the page displays the health code status, and the health code display is only 10s. If the ID number of the inquired person has not been declared, you can click "declare" to declare, or you can click "declare yourself" on the home page to declare.