Why is it pushed by epidemic big data without going out at home?

This may be because the attribution information of the mobile phone number of the communication operator is inaccurate.

If you have used a number and later cancelled it, but the operator's system has not been updated, and the current owner of this number has been to the high-risk area of the epidemic, the system traces back to the corresponding identity information, even if you stay at home every day, it may be pushed by the epidemic big data.

There is another situation that is more complicated. For example, someone goes to operator A to do a traffic package, and then goes to operator B to do broadband. Operator B gave him a card number for free, which is actually a secondary card. If people who use the secondary card have epidemic-related problems and are intercepted by big data, it will also lead to code change for people who often use the primary card.