Being told I must go to cell c repairs centre

I am very furious at ACKERMANS as I bought 2 cellphones cash at there Vangate mall branch and my one cell phone which is 6 months old just died.It didnt get in contact with water or anything that I can say I now why its not working. I then called the branch and took the broken cell to the store. Once I get to the store I was informed that they have a new procedure and I have to take the phone to cell c repair centre in Tygervalley. Im so upset as I wasnt told this when I paid cash for the phone on the day.If procedures change that had nothing to do with me.I will not go to cell c as I bought it at ackermans vangate mall.I will not incur any extra cost due to your change of policy. I want my phone repaired or my money back.