Hard Reset LG Optimus L7 II P713

First method:

1. First of all switch off your cell phone by holding the Power key for a short while.
2. The hold down the Volume Down + Hot key + Power button together for a couple of seconds.
3. When the LG logo is displayed, let go of the Power key and keep pressing the other buttons.
4. Release all buttons when LG logo disappears.
5. Now your phone should restart.
6. Success! The hard reset has just been completed.

Second method:

1. If the display is off hold down the Power button to turn it back on.
2. Afterwards go to Settings.
3. Select General and then Backup & Reset.
4. Then tap Factory Data Reset and Reset Phone. 
5. Choose Delete All if you are sure you want to clear all your data. 
6. Select OK to confirm the whole operation.
7. Well done!