guarantee issue

Hi just letting you guys know what bad service you guys have been giving my father. He bought an inverter in jhb and was told if there are any problems he may walk.into any branch. There seemed to have been a problem with it he then took it back to the kenilworth branch and they requested that he pays in a R700 for the repair of the inverter even though its still under guarantee. Its now been a month of countless up and down without any results. I think for a big name company like builders this service is very bad. It makes me feel like i need to protest infront of your stores to make people aware of how u actually treat people. Who knows mayb then you will get a wake up call? My father was promised a call back from the manager lionel and another guy by the name of micheal. Even the manager in the norwood branch, who said my father was not supposed to pay anytjing, promised him a call back but he hasn heard from any of them yet and was forced to run up and down to the branch and to date still no results. My father is patiently awaiting aome feedback concerning this issue. His name is Kamaloedien contact number is ***