Soft reset can resolve issues like continuous resetting/rebooting, device crashing, freezing, won't ring or vibrate, can't make or receive calls, device locks up, and keypad doesn't respond.
A soft reset is similar to restarting a desktop computer and is usually the first step in troubleshooting a device. In most cases, a soft reset won't affect data on the device, unless the battery is very low.
Press and hold the Power button.
Tap Power off.
Press and hold the Power button to power on the device.