Why can he send you a message when he goes to the electronic mall? How did he know your mobile phone number and what did he use to send it to me? Thank you. Just curious.

This is a wireless signal frequency search device provided by mobile operators to merchants. As long as there is this signal coverage near the electronic mall, advertisements and welcome messages will be automatically sent to you. This can be done without knowing the mobile phone number. Because it is controlled by the terminal signal. For example, a mobile phone roaming to other provinces will send you a welcome message. This is a truth, similar to the cell broadcast receiving function in mobile phones. You can turn off this function in your mobile phone, and some spam messages will not be received. I hope I can solve your curiosity, hehe.