Terrible Service!!

We have received atrocious service from Sinotec, our tv broke just little after two years and Master Audio Visual came to collect the TV on 11 August 2021 as it is still under warranty. When we called Master Audio Visual after two weeks for an update we were told that Sinotec did not send a courier to collect the TV from them and that it would need to be sent to JHB for further analysis at CN-Tronics. To date we have heard nothing more from them and when phoning the number *** it just rings and then cuts off. We do not even know where the TV currently is or when it will returned/replaced. The customer service is non existent.