The Phone Lock feature, helps prevent unauthorized use of the device by disabling outbound data and voice calls. The device will still be able to receive phone calls and place emergency calls to 9-1-1.
With the handset open and from the main screen, navigate: MENU > Settings & Tools > Phone Settings.
Utilize the 5-way navigation pad to highlight then press the center/OK button to select.
Enter the Phone Lock Code then select OK.
The default lock code is the last 4-digits of the mobile number.
Select Lock Phone Now.
For other lock options, select Phone Lock then select the desired option: