Solar man shop silverlake Terrible Customer Service

I bought a 1000w pure sine wave inverter for R3500 from Solar man Silverlake in Jan 2019. I had been using it for a month drawing about 300w max from it when 1 day it just stopped working. I returned it to them and they confirmed that it has a warranty, it has been 2 months nowl and after weekly going to the shop to enquire about the inverter and being told every time that they have been too busy to look at it I truly believe that it is some of the worst customer service you can find. I am contemplating legal action to try and get some response from them.