Bad service

My friend Swazi Buda bought a phone at this retail store in March this year by credit. She was told that it has a one warranty and if the phone breaks or has any technical problem they will fix it for her. In July the phone just stopped working she took it there and they told her she will get it back in six weeks time , however when she went to collect ,the screen was broken and they forced her to take it. She refused to take it and when she asked to talk to management she was told that its not their concern, she has been going up and down trying to get her phone back but they always force her to take the broken one claiming they can't help her. Please assist ..her numbers are ********** 961