I have had my phone 2 weeks now. I was using the phone in my living room and walked into the bedroom, The phone is in its case and I laid it on my bedside table and plugged in charger. When I came back to my phone, the screen is blank (black). The only way I can tell if it is even on is if I ask Siri if she is there and the answer I always get is either always or I am everywhere. This is all I get with a blank, black screen.. It was not dropped or manhandled..Please help me someone.