Power off the phone.
NOTE: If unable to power off, remove and reinsert the battery. Press and hold the Volume Up key and the Power key at the same time.
After the Huawei logo and Android Logo appear, a blue setting screen will display. Release the Volume Up and Power keys. Scroll to Wipe data/factory reset and press the Power key to confirm the Master Reset. Scroll to Yes - delete all user data and press the Power key to confirm. When the Data wipe complete is displayed, select Reboot system now and press the Power key to confirm reboot. The device will power off and back on.