Returned 1 product 3 times

I bought a vibro shappe belt from Makro, after few days it was no longer working and I took it back. They gave me another one, the same things happened and I also took it back and get a new one. Now I took back the third one and demanded my money but they refused and say their return policy say I can only get money back within 14 days, I understand their return police but for the fact that I had to take back the same product 3 times makes me angry and I want my money back.