Refuse to repair according to insurence

I bought a three piece lounge suite in July 2014 on account. The monthly instalment included insurance for the suite. After three months the stiches got loosen on the sides of all three pieces. I raised the complaint with their customer care and it took them 3 months to respond to this issue.<br> They fixed the stitching problem with the lounge suite. They brought the couches back after three weeks. <br> After about one month the same thing happen on all of them. The stiches came loose on the same place where they fixed it the first time.<br> I report it to their customer care and it took them a while to respond to this issue again. They finally came and collect the lounge suite. After a month I do an enquiry on the status of my couches. They eventually respond and give me an quote of R2400 to repair the coaches. When I asked them about the guarantee and insurance them they say this is not covered. Because of this I refused to pay them for two months now. They did a bad job the first time. When they phone and ask them about the payments, I explain everything and then they transfer my call to customer care. Then they drop the phone after 15min waiting. Please help.