At First Back Up your all impotent data than reset your call phone. when you will buy new call phone you need to know how to hard reset it. smart phone major problem is slowly working, hang, device is auto restart. don't forget backup your all impotent data after hard reset all data will be wipe.
For Hard Reset Battery Charge Need 70% Up.
1. Turn Off Your Call Phone Pressing Power Key.
2. Press and hold together volume up + camera + Power keys
3. When Device is vibrate only Release Power Key. keep pressing Volume up + Camera
4. wait few second device will be auto reboot and solve your problem.
On the Start screen, tap
Tap Settings >
Tap reset your phone,
and then tap yes.