Xiaomi's mobile phone number often receives advertising messages from Mengniu.

You have subscribed to Mengniu's advertisement.

Now the network information is very developed. As long as you buy his products in official website, you will leave your contact information. Many brands will send some advertisements as long as they buy things, which is also a way of advertising.

You can call the operator's customer service phone, ask to close the operator's marketing SMS port, reply to SMS unsubscribe, or download apps such as security guards on your mobile phone for interception.