Why is my iPhone not waking up when its fully charged

[iMore Question]

it worked a minuet ago and now it stop it is now pitch black and fully charged when my brother called me and it vibrates but won't wake up

 

[nikkisharif]

Press & hold the power & home buttons at the same time until the Apple logo appears. I've had this happen to me before & rebooting your phone using the instructions above should correct it.