I have a a56 phone and today that it fell on the floor, I checked for any cracks, and when i was checking i saw that at the top of my phone, between the sides and the back panel there was a black line, and wgwn i turned the phone upside down it went away from that side, but it appeared on the top again. I dont know what causes this. I have looked at it from many ways and I can confirm its not the angle im looking from. The line also appears at the sides aswell. Someone help