LCD FAULTY

I have a problem with the LG Service Center in Rustenburg VHS Video & TV Service. I took my LCD LG50LA6130 for repair after we called LG South Africa and they referred us to them as their service provider. The LCD went in as it was blank on the screen which they check and they confirmed it was the Back Lights they quoted me R3998.00 for the repair which they did do I was away with work for weeks and I came back on the 24March 2020 which was a day before lockdown I then collect the LCD. I they tested it which and I went home after I connect the LCD for the kids to watch and after and hour or two it started showing a line and as it gets hotter it started showing more lines I then I called they told me to bring it tomorrow morning which I did and I drop it off by them the ask me to come check it in the afternoon. I called the several times and it was not ready and since it was the last day 26 March 20 which the lockdown will be starting the following day. I went and lucky when I came in they said it was done and I ask the technician what was the problem he told me he doesn't know what happen but the screen was cracked but all was now well I didn't want to ask to much question and I took the LCD and went hope I connect it again and it played again for few and it went complete dead so the next day my wife contacted LG and explain to them what was the problem they asked us to hold on until the Service Center is up and running again.Thursday 07.50.20 I tried the number it rang and I ask if they were open and ask what was my problem and then explained and I was told to bring the LCD again to check on my arrival I offload the TV and the shop assistant help me and test the LCD. And the owner said to me that they are going to book the LCD in as this was no longer the same problem that the TV came in with at first he ask me to pay a R100 and he started being defensive when I ask him how does want me to accept me pay R3998.00 for a LCD that played less four hrs and expect me to pay more. I explained to him why my suggestion were on this matter but he would listen and he wanted me to pay the R100 for checking the very same unit that came to my house for less than four hrs. I want to tell LG that I want their service center to take back the parts on the unit and give back my money since they saying this is not their cost. I ask the guy if we can do the rechargeable he refused and his very rude and my wife called him and ask him remove the parts and take the labor and he refused and say his not going to refund us he has done the job and we can go wherever we want his not going to give back the R3998 I want LG to give back my money