Bad service

I Beema Maharaj had taken out a contract with Nashua mobile before the company closed down and they then handed over Cell C contracts to Altech -Autopage. I had a problem with my battery swelling and had gone to the auto-page in pavilion they were very unhelpful and sent me back and fourth to the Samsung offices in Nandi drive and Nothing was done. We needed a new battery, I had misplaced my original contract documents but asked that auto-page please find the copies that were handed over by Nashua, they said they would locate it and get back to me, they have not located it because I am still waiting for their call. The period for the guarantee expired waiting for some feedback.I bought a new battery myself the Same thing happened with the new battery and I think its a problem with the phone. I am paying a contract where the phone is not working. I have to use my daughters old phone they are unhelpful and refusing to replace it because I have misplaced the originals they have copies and lazy to locate it I am on the system and a contract customer is that not proof enough that I have taken out the contact with that specific phone? Their excuse is Nashua didn't give the documents.