Frequently, I am receiving calls and am unable to answer the calls because the touch screen will not respond when I try to scroll down and unlock the screen. Even more frequently, I touch my face to the screen when I am in the middle of a call, and this will activate the screen and end the call. Often when I am searching contacts and put my finger on the scrreen to scroll down through the list, the phone will call the contact that is nearest to the place where I touch the screen. I am very frustrated. Does anyone else have these problems? Please help.