Game stores Welkom nightmare

How to improve... mmmm I need a book for this. I bought a microwave at game 2020 so just out of warranty 7 days it broke not heating up anymore (Russel hobs) So bought a new one the same one cause thats the only 40liter Russel hobs in store 6 months now same problem not heating up anything. I went to game to tell them the problem telling me they will send it 2 Russel hobs and will take 21 days please take note I have a baby in the house.... never the less. I told them I can not buy a 3rd one costing another R2000 in 6months and I can not go without one. So they tried heating up water im not sure how long well it heated up but the microwave on the outside is as hot as hell so something is wrong. Sending me home with a broken microwave telling me theres nothing wrong with it. GUESS what Im at home trying to heat my baby's bottle and nothing. So what am I supposed to do?? I told the lady so I guess im coming back the whole time till my microwave is out of warranty and then what?? then nothing she rep****....