Joke Collection Website - Public benefit messages - How is it that telecom mobile phones can send short messages but can't receive them?

How is it that telecom mobile phones can send short messages but can't receive them?

1 Check whether the software with SMS interception is installed on the mobile phone: 360, security housekeeper, etc.

Test card, take it out and put it on other mobile phones to test whether the service is normal, and then put another card on the mobile phone to test whether it is normal.

The service of card 3 is normal. Take the mobile phone to the business hall to check and see if it can be solved.

4 still can't restore the factory or brush the machine to try.