Samsung Sent Me a 55-inch TV Instead of the 65-inch I Requested

I bought a Samsung 55 MU7400 series TV. The panel malfunctioned, and it was replaced under warranty. After a while, I experienced the same issue with the new panel. My warranty had expired, so I contacted the service, and they informed me that the panel was no longer being produced. The TV I purchased is 7 years old, but legally the company is required to produce parts for these products for 10 years. They did not fulfill this obligation, which is the first issue. Then, the service offered me a new model TV if I paid ₺15,000. I made the payment, but without consulting me, they sent a new 55-inch TV. I refused to accept the TV and requested to exchange it for a 65-inch model by paying the difference, but my request was denied. The representative who called me said that they do not sell TVs, and therefore I cannot pay the difference for another model. What I don't understand is, if they asked me for ₺15,000 and sent a TV, isn’t that considered a sale? I live in Adıyaman and, as someone who has faced all the negative impacts of the earthquake, I complied with the company's request without objection. So why wasn’t my request fulfilled? I really didn’t expect this from such a reputable brand. When they insisted that my request couldn’t be fulfilled, I had no choice but to accept the TV they sent. Unfortunately, they forced me into this situation.