Hi Trains,
Well it's really hard to say anything about that, unless someone here is an expert on phones and you can present him or her with more detials, like brand, type, etc.
I don't know where you have bought it, or if you have a warranty, but I usually go back to the store and they'll send it to the factory where they fix what is wrong, if something is indeed wrong.
They'll be able to assess the situation for you, at the store, but again, this only works if you got it that way aswell.
Fred