how do you fix the touch screen of a Samsung impression, i just got the phone but there's a problem with the touch screen ,every time i turn it in there is a gray screen that has a white cross, it says to tap the center of the target as it moves but the screen must not be working because every time i tap it it doesn't respond, when it locks i can see the background in color, sound is good but every time i unlock it it just goes back to the gray screen, what do i do this is my first time ever having a phone so im a noob to this