You often see this situation, and so does my friend. The reason may be that when you handle the mobile phone business, the mobile staff kept a copy of your ID card, and then they took the copy of your ID card to help other customers who did not provide their ID cards to handle the broadband business.
This kind of moving behavior seriously violates the customer's personal privacy, revealing and improperly using the customer's identity information. You can complain to the mobile customer service hotline, complain to the industrial and commercial department 123 15, or report the case directly.