Most pathetic and worst service ever

I had returned a heater before the guarantee had ended , when I took it back I explained to them that the heater was giving me a problem . It works sometimes and then somedays it doesn't work . It doesn't come in for like 2 or 3 days. The manager had told me he would get bk to me , he called me the next day and said it is working , and I told him again it works in certain days and then stops . I foned a couple days later to the customer care and spoke to them they told me they calling the store , spike to the manager again he told me the same thing which he gave me alot of attitude and then told me that he will give it to the supplier , I told him to call me and let me know what they say and it's been 2 weeks and no call ,I called today and asked them ,the heater is still there with the same excuse it's working,y in the hell would I return something that's working , the most pathetic service and most pathetic attitude from pick n pay southgate. Now I either want my refund or a new heater