In most cases, random restarts are caused by a poor quality app.
1 Turn the device off.
2 Press and hold the Power key past the screen with the device name.
3 When ‘SAMSUNG’ appears on the screen, release the Power key.
4 Immediately after releasing the Power key, press and hold the Volume down key.
5 Continue to hold the Volume down key until the device finishes restarting.
6 Safe mode will display in the bottom left corner of the screen
7 Release the Volume down key when you see ‘Safe Mode’.
phone doesn’t restart on its own in safe mode, then it’s confirmed that one of the apps you installed is causing the problem.
//Can't go to safe then it's corrupt software//
If you have installed an app you suspect is causing this problem, then find it, clear its cache and data and if that won’t work, then you have to uninstall it.
2- System Apps Are Disabled
Did you play around with disabling Android apps? If you went too far and disabled apps that are required to run the Android OS, it may be causing your restarting issue
3-. Overheating
Many Android devices are designed to shut off automatically if they become too hot.
4 – Loose Battery
Of course, this problem only occurs on devices with a removable battery.
5 - Corrupted System Software
reset the device. *Back up before reset*
/Setting-general management-reset-factory data reset/
nothing works goto Samsung service center for any hardware problem.
