My phone keeps going back

[Danmad]

My home and back stopped working i have been using virtual keys now my phone keep taking me back whenever i open an app

 

[Rukbat]

Home ans back are usually part of a little sub-assembly at the bottom of the phone. It sounds as if that assembly has to be replaced. The assembly usually isn't too expensive, but you'll have to pay for the labor of replacing it. I strongly recommend that you don't try to do it yourself.