Lack of service, pointless guarantee

On the 13.01.2014 we purchased a Grafton Everest Nebraska lounge suite cash. Had it for a few months and the seats started sagging in, we assumed that the sagging was normal as we thought the coushions were setting. Eventually we noticed that it was more then that and uncomfortable. It January my husband contacted the store and was told that nothing can be done as it Is outside the guarantee period. My mum then contacted the store and was told she needs to come in with the purchase documents, the consultant advised that she can't guarantee resolution but will look into it. I eventually phoned the JDG call centre and was told by Malibonsiwe, that they are a two year guarantee store and will contact the store and get back to us. This was a week ago. I can't believe how difficult it is to get some help. Seems like the JDG brand is truly unreliable.