How to lock the mobile phone card

If you use a vivo phone, the SIM card lock unlocking method is as follows:

Go to Settings-Security/Safety and Privacy-(more security settings)-Set SIM card lock-Open "Lock SIM card"-Enter PIN code (default: 1234), and you need to enter PIN code every time you start up after booting.

(Enter settings for some models-(More settings)-Security-Set SIM card lock-Turn on "Lock SIM card")

If you have more questions, you can go to this link page to consult online customer service for details.