Have you ever encountered a situation with you phone where it hangs and the sensor cannot function anymore? Then you try to turn it off and it doesn't, and since the battery is in-built you may run out of options on what to do.

Well not to worry! Before you start breaking off your glass screen guard in fear & worry, you should probably try out this easy fix.

Press the power button in for about 40 seconds for it to automatically reboot by itself, in some cases it may switch off, then you turn on the phone and voila, the sensor would start responding.