Why my phone is restarting by itself or shut down?

[Xcel98]

I bought my phone one week ago and everything was fine for 3-4 days.
After that, it started to restart itself or even shutdown for no reason.
It even restarts when i leave it alone on the desk, also i got woke up at night by this cause.
My phone restarts 2-3 times per 1-2 days , but in the night it restarts like 2 times continously.
Please Help !!!
Thanks So Much !

 

[johnkingx]

Sounds like an app is causing this if everything worked fine in the beginning.

Could you start your device in Safe Boot to see if the problem persists.

Ensure your device's screen is on, then press & hold the Power button.
Touch & hold the Power off option in the dialog box.
Touch OK in the following dialog to start safe mode.

If the problem remains I will suggest to do a factory reset to see if that solves the problem. If the problem disappears it confirms my thought that it is app related and I would recommend uninstalling apps you recently installed or updated.

 

[Carlos Paul]

I suggest you to go to the store where you bought it, every store has a 15 days product replacement policy, if not, try do a factory reset and check if there is a battery problem.