The round copper contact under the button that flexes and connects two wires on a ribbon has fallen off the ribbon. they are $13 for the tiny item online(google). you will need a t5 tork to open the back cover. you will also have to peel the speaker, camara, and antenna covers off to get to the screws. they are $5 each to replace and the sticky will not save. search youtube for a video show exact steps to open. Best left for someone with experience working on phones.