A hard reset, also known as a factory reset or master reset, is the restoration of a device to the state it was in when it left the factory.
All settings, applications and data added by the user are removed.
The term is often heard in reference to smartphones and tablets but laptop and desktop computers, as well as most other electronic devices, can usually be restored to factory conditions.
1. For our first step you will have to turn off your phone.
2. Now please press and hold Volume down + Power button + Home button and keep holding them untill next step.
3. Wait untill LG logo will appear on your screen then release the buttons.
4. There should appear Factory Reset screen looking like this:
5. Using the volume button choose between the option and confirm with power button.
6. Please choose "Yes" option and your phone will restart, after that you can work on device.