Disgusting service from HiSense

I bought a TV at Hi Corporation and i have had problems with it from day one. You can't watch youtube and it freezes. I have had Hisense technicians out 5 times to come and have a look at what the issue might be. They put a new brain into the TV and it is still the same. Last week Monday they came to fetch it for testing. I took a video to show them how it freezes and that you can't do anything. I have to switch the power off at the wall plug. Then put the power back on at the plug then put the TV on. They have it now and when I phoned about it they say that there is nothing wrong. I spoke to a consultant on Friday morning to enquire about my TV and was assured that a technician would bring it back on Saturday the 1st of February 2020. That never happened and when I phoned to find out what is happening I get told that they will check with the technical team and let me know. That also never happened. I sat on the phone for 2 hours waiting for someone to answer my call. I phoned the guy that come and took my TV in and asked him if he was bringing my TV back on Saturday the 1 Feburary 2020 and he told me that no one was working. So from Friday and Saturday the people at the service center have been lying to me. That's the services you get from hisense. The service provided from HiSense and their team is absolutely disgusting. Our TV is only a year old and have had endless issues from the beginning - yet anyone from HiSense are reluctant to help or simply return a phone call.