Terrible customer service from Makro

I bought a Hisense oven from Makro Woodmead on 23/06/2022. It had a 2 year warranty and we bought an extended warranty for R940 which is valid for 3 years. On the 10th of July 2024 I logged a call with the contact centre to advise them that the oven doesn't heat up. They only assigned it to someone to come out to have a look at the oven on the 15th of July and he only came out on the 18th of July. He then advised that it is the thermostat. Since then they have not come back to me to give me any resolution as to how they are going to fix this!!!!! I spoke to the company they assigned it to and Hisense. Hisense advised that they do not have stock of the thermostat and eta is 30/09/2024. No one from Makro is coming back to me with feedback or coming back to me with a solution. I have explained to them that I need my oven to bake my orders and I'm loosing money as I cannot take in orders currently due to the fact that my oven is not working!! I have asked them to take a thermostat out of an existing unit to come and fix my oven, or they need to bring me a new oven or refund me the R940 for the extended warranty so that I can fix the oven myself. However, no one from Hisense or Makro is coming back to me and I'm loosing money daily!!! I have to phone them to follow up and have to hold the line for 10-15min at a time then they make notes and promise they will come back to me but never do!!! At this point I just want my R940 back that we paid for the extended warranty so that I can fix the oven myself!!! Hisense told me that they do not give extended warranties on ovens so if Makro gave the extended warranty then it is their problem!