Ghosted by company

I purchased an item online from “Alloutdoorandhome.co.za” aka “Lesandre Online Pty Ltd”. It was a Typhoon camping stove. Since I have started using it, the flame is too high and everything burns. I have spoken to Lesley. She first gave us the manufacturer’s number but they couldn’t assist. She then told me we spoke to the wrong person and she would contact them. So far no luck. She is not responding to my messages. All I want to do is return it for a refund. I feel it is dangerous as we smell gas quite bad while using it. I don’t have another stove so I am forced to use it as unsafe as it is. I am extremely unhappy with their service. Quick to sell you an item, but then they cut you off when there is a problem.