At First Backup Your All Data. make Sure your Device Battery is Not Empty. Remove Sim Card And Memory Card.
1. Make Sure Your Device is turn off.
2. Press And Hold Volume Down Key + Power Key To Turn ON your Device.
3. When Show logo on screen only release Power key. keep pressing Volume Down Key until Release all key appear recovery menu.
4. than Select wipe data/factory reset Power Key To Confirm.
5. Select Yes-- Delete all Data
6. After That Wait Few Second and Select "Reboot System Now" Press Power Key.
Device will be Auto Restart and Solve your Problem.
