Scroll down and tap on Backup & Reset (may be listed under "Personal" or "System").
Press the Power button to go back to the main menu. Then select Reboot → Reboot to System . How to Hard Reset MEIZU M5
Read the warning carefully. It will list all the data that will be erased. Scroll down and tap on Backup & Reset
Confirm your choice. A warning will appear. Use the volume buttons to select OK and press the Power button. How to Hard Reset MEIZU M5