Useless Hi Sense Electronics

I purchased a new one 55" television, and model number is 55K390PAD on 21/11/2014 at Hi-fi Corp and The Glen. My transaction number CA***. This included complete payment is on extended guarantee. Last year November 2020 the set just went completely to the blank. I contacted the hi sense directly and was given a technicians number of the which to make contact with and advised me that the call out fee would be a minimum of R450.00 excluding repairs. I contacted the the technician, but they however said that my enquiry being does Hi sense products only last as long as the warranty validity regardless of price. The in 2011 I had the same issue with a television set purchased of which Hi sense could not fix the television. I had to discard the TV after having spent money doing the run around. I do require a assistance in the asap as this is **************** even after having paid everything in cash. Please contact me on *** at any time. Thank you