FOSCHINI WITH CHEAP MATERIAL AND LOSE STITCHES

I bought a blazer at Foschini and hardly even wear it, the stitches came lose on the 6 to 7 month, they refused to take it back even with the proof of purchase I still have. I'm not happy with their quality and its not the first time I returned their blazers but this time around they refused. I layed a complaint with their customer service thinking that would help, only for them to escalate the issue to the people at the store (those that refused to take the blazer), how do explain that?