Poor service for return/fixing of damaged goods

I visited House & Home Kimberley last year 2018 May to purchase a very gorgeous L shaped couch, I believed that it would be a great buy because I had seen how beautiful my friends new couch was which she bought there, the staff were very helpful and all hands were on deck for the sale they only had good things to say about the couch, 3 months into having the sofa it broke in the middle due to not having any support on the bottom, it's a fairly big couch and only has support at the corners but completely vulnerable in the middle, I called my sales agent to let him know and it took a further month and a half before they acted on it and this was after the manager had become involved in the matter.. This is around December, the sofa came back around January /February 2019, I thought okay I can start enjoying it now, little did I know that this couch is completely useless, around end of May it gave it again, now together with the other part of the couch.. I've been contacting the store since yesterday (1st July) and keep getting the run around and nobody is getting back to me about what I should do with this couch which I ensure to pay fully and never go into arrears, for my loyalty and commitment to this store this is the thanks I get, today on the 2nd I first had to scream and shout over the phone for the manager to take control... If this is not resolved by tomorrow I will personally go and drop off this sofa infront of their store and cause a scene.. I will not make payments on this sofa and we can deal with this by law.