Faulty inverter, returned 5 days, now a month

I bought a 1200W Ellies inverter for R7000 on 18 April. I set it up as instructed running 1 TV, DSTV and a laptop. Worked perfectly with load-shedding for 4 days then stopped working with an electrical burning smell and a continuous alarm on the 5th day. Returned immediately, told it had to go back to the supplier for evaluation but, seeing that I had just bought it, they would try to rush it, but at most about 10 business days. On the 8th business day I received a text saying it had got to the supplier. Since then, now 18 business days and nearly a calendar month, I am still waiting. Went to Makro on Saturday and, after no help other than that it was not ready yet, I requested the manager. I got the manager of customer service who said that they would check on Monday. I was phoned on Monday, 3pm, to be told that they were waiting for a response from the supplier, Ellies, who are still evaluating it. This inverter stopped working, full stop.