So about a week ago, my phone has been doing weird stuff by its self lately. So what happens is that sometimes when I unlock my phone, the phone would freeze and when I touch the screen, the screen would not respond. When this happens, I press the power/lock button to lock the device. Doing this results in the phone turning off by its self and I would have to press and hold the power button for 5-10 seconds for it to turn on again. I have done a battery pull a few times when this had happened, but problem is still not solved. My phone is not rooted and all apps I have installed are safe. Please help me with this problem.