UPGRADE GONE WRONG

I received a call from Nicolette Naidoo in the middle of October asking me if I wanted to upgrade. I agreed and we confirmed a 24 month contract for an iPhone 6S. The phone arrived and it was on a 36 month contract. I subsequently waited for an hour at a MTN direct store to return the phone and to try cancel this contract. Once cancelled which took about a month after many irate emails for the cancellation to happen, I gave Nicolette another chance and said she can supply me with the Rose Gold iPhone on a 24 month contract. She confirmed they had stock and apologized for her previous contract error. Last week I received the phone and it was the wrong colour, it was a gold phone. I sent it back and refused the delivery. I sent her an email to ask her to rectify, which I am still waiting for an answer. I then called and asked to speak to her supervisor, which refused to take my call so the person answering the phone said she would relay the message. To my surprise, the courier walked into my office today which I thought was with my new rose gold phone and couldn't believe that MTN tried to redeliver the incorrect GOLD phone! I am speechless and want to migrate my contract