Perform a soft, factory, and alternate master reset of the device.
INSTRUCTIONS & INFO
There are multiple ways to reset your device if you are experiencing issues. The first step is to power cycle your device. Press and hold the Power/Lock button, then tap Power off. To turn the device back on, press and hold the Power/Lock button until the screen lights up. Note: If you are unable to power your device off or if it becomes unresponsive, press and hold the Power/Lock button for 10 seconds, until it reboots.
To perform a device restart, press and hold the Power button, then tap Restart. Note: If you are unable to access the screen to 'Restart' the device or if it becomes unresponsive, press and hold the Volume down and Power buttons simultaneously for 10 seconds, until the device restarts
To perform a factory data reset (master reset), swipe down from the top of the screen, then tap the Settings icon. Note: A factory data reset will revert 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. It is recommended that you save (backup) important data before proceeding.