A master reset will result in the loss of all data stored on the device including 3rd party applications. Please, follow the next steps:
1- With the device powered off, press and hold the Volume Down key. If Device Protection is not disabled, the login credentials for the Google account associated with the device must be entered to complete the initial setup.
2- While holding the Volume Down key, press and hold the Power key. Release both keys when the Recovery mode screen appears.
3- On the Android Recovery screen, press the Volume Down key to scroll to and highlight Wipe data/factory reset.
4- With Wipe data/factory reset highlighted, press the Power key.
5- Press the Volume Down key to scroll to Yes, and then press the Power key. Once the wipe is complete, press the Power key to select Reboot system now.
6- The device will restart.
7- The master reset is now complete.