Turkish Airlines Ticket Cancellation Problem

I'm completely fed up with Turkish Airlines. I bought an international ticket with the promise of a free cancellation. I even paid an extra 6,000 for this feature, only to discover that I can no longer cancel my ticket. This is entirely unacceptable. Despite my numerous attempts to contact Turkish Airlines, they have been unhelpful. They clearly do not want to honor the free cancellation I paid for. At this point, I have no choice but to file legal action to resolve this matter. It's very disheartening when an airline fails to keep its promises, and I hope my experience serves as a warning to others who are experiencing similar problems.