Poor After Sales Service

I bought a flagship TV (model 65U8A) in 2017 for an eyewatering amount. The performance of the TV set was brilliant and I absolutely enjoyed it. As it is ageing now, the backlight is now on it's way out. I have called the Hisense call-centre for an out of warranty repair. I was sent to 2 service providers, Mikerolight TV Repairs and TG Vision TV Repairs. Both providers responded that they are unable to repair this TV because the backlight is unavailable from Hisense. This is completely unacceptable. What this means is that I will now need to buy a whole new TV. I think that the product is very good, but the after sales service is very poor, and for that reason I will not recommend this brand. Should I replace the TV it will be with another big established brand.