Please help me get my hard earned money back

On the 23-06-2023 at 14:50pm I went to Cash Crusaders N1 City to lay-buy an electric heater Dixon SYH-1505S. Stock code : ***6S1721 / nogkg. Serial : dn***. This heater was worth R899.90 at the time and I paid R450.00. I then returned on the 25-07-2023 at 09:29 am and paid R449.90 to take my new heater home. It did not last even a week until I had to return the heater as it was faulty. The flame light in front which is what attracted me to buy it was no longer working but it was still producing hot air. I was then given a new heater and it was tested in front of me and it was working fine. The same problem started again after a month but this time the heater was no longer producing hot air but room temperature air. I took it back to the shop on the 12-09-2023 at 17:32pm and I demanded my money back which I was refused but I was advised that they will take it to the repairs and I have to wait 7 to 21 days. They called me after 24 days to come fetch my heater from the repairs but I was only able to go fetch it this Monday 13-11-2023. I got there and they brought it out from the box to test it before I take it home and to our surprise the heater now is tripping the whole electricity supply at the shop! A problem it never had before. I was told that they will take it to the repairs again. I told them I want my money back because I no longer work at N1 City and I have to spend close to R70 as a return fare just to be told it's not working. I demand my money back from them. Please reach out using my email *** or my cellphone number *** for any further information.