Why do I often get some untitled messages that I can't open on my mobile phone?

When you turn on Monternet service, you will receive some advertising information, which is inevitable unless you turn off all services.

Personally, I think the message that can't be opened is MMS. There is something wrong with your mobile phone settings, so you can't automatically accept MMS. Please confirm that the MMS settings are correct, and I hope my guess is correct.