Phone freezes while restarting

try wiping the cache partition this will give you a clear cache for a clean boot. Factory resets don't clear the cache and its apparent the boot loader that's in the cache is corrupt . To do this shut the phone off completely then hold the power button and the volume up at the same time once it powers on release the buttons and it should take you to the android system recovery .Navigate to wipe cache partition by using the volume button and when you reach the wipe cache partition press the power button to select then once it completes select reboot system now and then it should work . If this brings no joy then you will need to try updating from the same menu and if it still doesn't work then you will need to load a new ROM. Hope this helps