Find "Change PIN 2"
Slide your finger down the display starting from the top edge of your phone.
Press Settings.
Press Settings.
Press Security and Privacy.
Press SIM Card.
Press Change PIN 2.
Change PIN2
Press Enter current PIN 2 and key in your current PIN2.
Press Enter New SIM PIN 2 and key in a new 4-digit PIN2.
Press Confirm SIM PIN 2 and key in the new PIN2 again.
Press OK.
Exit
Slide your finger up the display starting from the bottom edge of your phone to return to standby mode.