To set up a SIM card lock for your L722DL, follow these steps:
- From the main screen, tap the "Apps" icon.
- Locate and tap the "Settings" icon.
- Tap "Lock screen & security."
- Locate and tap "Set up SIM card lock."
- Tap "Lock SIM card."
- Enter the default PIN 1111 or 1234. Then, tap "OK."
- Tap "Change SIM PIN."
- Enter the current PIN, then tap "OK."
- Enter your new PIN, then tap "OK."
- Enter your new PIN again to confirm, then tap "OK."