Breach of Contract

I am a cell c customer with a contract that's about to expire, since I was due for an upgrade I contacted cell c for an upgrade, I spoke to Nathi and he offered me a AG Ghost which we agreed on, but my issue now is he has opened a new contract for me where he was supposed to do an upgraded. I make minimum wage I cannot be paying almost a R1000 on cellphones. I have contacted cell c but no one is able to assist me, I want an upgrade not a new contract, I am a very unhappy customer, I need cell c to come and pick up the phone that they delivered as I will not be able to pay for it, if I cannot get an upgrade as i requested then let it be I do'nt want a phone that I cannot afford.