LG Optimus L7 II Benutzerhandbuch Seite 119

8. When the screen freezes
If the screen freezes or the phone does not respond when you try to operate it:
Remove the battery, reinsert it, then turn the phone on.
OR
Press and hold the Power/Lock key for 10 seconds to turn it off.
If it still does not work, please contact the service centre.
17