Damaged phone

I bought a phone at Foschini Group a while back. Then it started to give me issues and I took it to Foschini and they said they will take it to the supplier. At the time I took my phone to them the issue was the software problem. Then I was told the techinicians of the network rejected my phone is returned it because the memory cards slot was broken - but at the time I took it in the memory card slot was fine. Now Foschini doesnt want to take responsibility/ sale person who took in my phone - and the supplier wont fix it unless it gets to them without being broken and on the slip the problem was the software issue not a memory card slot broken. Please help.