Cell C
Don`t want to change a faulty fone

I went to O R Tambo Cell C to exchange my faulty Blackberry Z10. The staff then send me to their headoffice who in turn send me back to the store with the understanding that the store would change the phone for another one.
That is where everything went wrong. They said that its out of their exchange period but I explained to them that I thought it was the network that was bad and not the phone. I only suspect the phone as soon as i tested the sim in a old Nokia and the signal was perfect.
I then spoke to Their Reginal Manager who tried to make me feel like an fool. All I wanted was for them to change the phone.