Bad service from Samsung

Bought a Samsung 55" smart TV. In less than a year it needed a screen replacement which was done under guarantee. The replacement screen was from the beginning an issue, had a thick sticky substance on it which the technician came back and removed it. After that it's still have white shadow spots in the corners which have been told by technician to send him photos as proof. Camera don't pic it up! Now the TV is having another problem, called Samsung who sent a technician which diagnosed an *******ed motherboard. I complained about it and requested a replacement TV which I've been told had been escalated to management and there response is that they can only replace it after 3 or more repairs. The TV are still under warranty. This is not the way to go. Keep on replacing the parts. Samsung don't care about clients and their happiness with a product. Everyt time when speaking to an consultant they say it's been escalated but the response from the management is the same nonsens