Makro and Defy

I bought a stove in January from Makro which was installed by a company that Makro has a contract with, mind due you pay for that service separately. Makro says once you buy a Defy product from them they will not handle any problems that come with the product, but we have a 5 year guarantee?. I have contacted Makro to review the stove we bought but could not use as it doesn't work and no assistance was received from them. Tried logging a call with Defy but still no assistance whatsoever. None of them seems to want to take responsibility. The Makro manager for the stove section was very rude. I knew instantly that my matter would not be attended to. What do we do?