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. To begin, turn off your device.
2. Now press hold and press Volume Down + Power button.
3. Wait untill factory data reset screen will appear, it should look like this:
4. To proceed further navigate with volume keys to move up press "+" or down "-" and to confirm press power button.
5. Press on "Yes" when you will see message that says "Erase all user data & restore default settings?" to finish your hard reset.
6. Congratulations! you have finish the whole proces.