This article describes how to reset the device to its factory settings.
INSTRUCTIONS & INFO
A master reset reverts the device back to factory settings. It will permanently erase all personal data, preferences, settings and content such as pictures, ringtones and apps that are saved to the device. Data stored to an SD card will not be erased unless otherwise selected. It is recommended that you save (backup) important data to your SIM, SD card, or a computer before proceeding.
From the home screen, swipe down from the top of the screen to access the Notification menu.
Tap the Settings icon.
Under System, tap Backup & reset.
Scroll to, then tap Factory data reset.
Tap Reset device.
Tap Erase everything.
If unable to reset the device using the above steps, try the alternate master reset method by first powering the device off.
With the device off, press and hold the Power/Lock key and Volume up key.
Use the Volume keys to scroll down to wipe data/factory reset.
Press the Power/Lock key to confirm.
Scroll to Yes - -delete all user data.
Press the Power/Lock key.
Select reboot system now, then press the Power/Lock key.