Find "Change barring PW"
Press the Menu key.
Press Settings.
Press Call settings.
Press Call barring.
Press Change barring PW.
Change barring password
Key in the current barring password (default is 0000) and press OK.
Key in the required barring password and press OK.
Key in the new barring password again and press OK.
Exit
Press Disconnect to return to standby mode.