The security code for the Nokia 3120 Classic can be used to block certain functions of the phone. You can restrict calls and block access to the phone’s SIM card using the security settings.
Changing the security codes for the phone helps to ensure that someone cannot access certain functions of the phone without your permission. You do not need to download any special software to reset the phone’s security codes.
Press the “Menu” key on the Nokia 3120 Classic’s home screen. Select “Settings” and select “Security Settings” from the list of available options.
Select “Access Codes” and enter the security code for the phone. By default, the security code for your phone may be “12345.” Select “Change Security Code” and enter the new security code for your phone. Re-enter the number to confirm the change. Press the “End” key to exit back to the phone’s home screen.