I slept at 1 am and it was still half charged and when I woke up at 6 am it didn't open. So I got nervous since its brand new. I tried to do the stuff the manual said when the phone freezes or experiences fatal errors. Anyway, how come the battery's charge suddenly went from half to zero? Is that normal for a Samsung phone[I am new to Samsung.] I am certain that I had put it in standby mode before I slept. The only thing I did was to set the alarm.