Bad Service Bad Attitude No Responce

So long story short is that my tv set was taken in to have the screen repaired after many phone calls and much time lapsing. I informed Robin that the screen was faulty as well as he should please check the usb ports. He promised that this would be done and the report would be sent back with the TV. The tv set came back but no report and no follow up call made to make sure everything was in order. After about a month and a half maybe my brother decided to now connect his x box. Now the sound port was not working. This was never an issue as he used to have the DVD player, DSTV and his X box connected to it before. And had at the time only connected the DSTV. So as I returned for business to KZN my mother contact Hisense again. They send a technician out and he took done some details and said he would return to replace the part. Eventually he did. Only after two to find out that the serial number on my slip of purchase and the TV set now did not match. He took photos and said it would be sorted out. I have since logged calls and Facebook messages and no one has resolve the story of the serial number. they have done a temporary fix and no calls back. Dissatisfied and angry!!!!