Joke Collection Website - Public benefit messages - How does Redmi 7 enter the self-service card?

How does Redmi 7 enter the self-service card?

Prepare two mobile phones, A and B. A is a 4G mobile phone. Insert the USIM card into the card slot and keep it turned on. At the same time, make sure that the SIM card being used is in the mobile phone B and B.

4G smart phone A will receive a short message from 10086, reply to Y, wait a moment, and the phone screen shows that the card writing is successful. Click OK.