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. Lets start from turning off your device and waiting few seconds.
2. When you have powered off your phone, please press and hold both volume down + power key
3. Now wait untill hard reset menu will show up.
4. Once you are here, use your volume keys to navigate and to confirm press power button, so please choose wipe data/factory reset option.
5. Hard reset is complete, now wait untill phone will finish rebooting. That's it!