1. 1. Find "Set up SIM card lock"
Press Security & privacy.
Press More settings.
Press Encryption and credentials.
Press Set up SIM card lock.
2. 2. Turn use of PIN on or off
Press the indicator next to "Lock SIM card" to turn the function on or off.
Key in your PIN and press OK.
3. 3. Return to the home screen
Slide your finger upwards starting from the bottom of the screen to return to the home screen.