Samsung 65Q80B TV Had Three Motherboard Failures but I Still Got No Replacement

I bought a Samsung 65Q80B QLED TV, which broke down, and the service team said the motherboard was faulty. Even though I requested a replacement, they repaired it and returned it. Three months later, it broke again with the same motherboard issue. I again asked for a replacement, but they repaired it and gave it back. Now, just four days before the warranty expired, the TV broke down once more, and they said they would replace the motherboard and return it again. I clearly stated I wanted a replacement, but their response was, “Your warranty has expired, we can’t replace it, only repair it.” Despite requesting a replacement while it was still under warranty, they refused, and now they use the warranty expiration as an excuse. How can a TV have a motherboard failure three times? What a waste of money.