Why is my health code red? The person next to me didn't change the code.

You may also, for example, if you are a close contact or a sub-close contact, your health code will turn red. And the person you have contacted becomes a second close contact, and it is normal that the health code does not change color.

According to the Regulations on Epidemic Prevention and Control, the health codes of suspected cases, confirmed cases, recurrent cases, close contacts and sub-close contacts of asymptomatic infected people will turn red.

So the second close contact will not turn red.