I am using a cell phone Nokia 5800 Xpress music which is a symbian phone. It has many features such as 3G, TFT capacitive touch screen, 3.15 MP camera, Wi-Fi, GPS and many more. I liked its functions and features and I was satisfied with it. In the beginning I never faced any problems but after some time I noticed that proximity sensor is not working properly. The phone works as it is supposed to work but when I make a call, i.e. the screen goes off when I hold it to my ear. While having conversation with someone through my phone I usually press the mute or loudspeakers buttons with my ears touching the phone since the screen does not lock during conversation. Sometimes when I call someone and if any part of my face touches the screen then the call gets ended automatically and sometimes it completely stops working. Is my proximity sensor dead? If not, then how can I activate it? How can I solve this issue?