Galaxy S4 keeps shutting down on it's own.
Several days ago my Galaxy received a system update that really changed how the device looks. Apparently, also how it acts. When it sitting next to me I notice it restart on it's own. Sometimes when the blue notifications light is flashing, I attempt to press the hold button but all I cannot get the screen to show itself. Sometimes I have to remove the battery and restart it in order to continue using it. Sometimes I merely press the power button to open to the lock screen, and it restarts, even though I have not been holding it for the correct amount of time for it to do so. I have not had time to call support. I am hoping there is a simple fix or way to uninstall the last update; but I am not sure how to do so. Please help! In case of emergenct this thing is my life line and I would hate to think that it could end up failing me. Especially when I pay so much for it.