Terrible customer service!

I am so annoyed with the service I've been receiving from Makro I've been waiting for a refund since the 23rd August to date bought a heater and it leaked oil they changed it 3 times but the 3rd one still done the same thing and i opted to get a refund instead, the heater was collected but it's been over a month that I'm waiting for my money, I've been calling every week, i went into one of the stores but they referred me to the call center who keeps giving me different stories, I'm disappointed that such a big company is giving me such bad service.