Turkish Airlines Primefly Cancellation Fee Issue

I purchased a Primefly class round-trip ticket from THY for my Milan flight for ₺9426. Despite cheaper options, I chose this because the description mentioned free cancellation. Due to visa process complications, I specifically chose this ticket model as it stated free cancellation up to 12 hours before the flight. However, my visa was not approved, and when I called THY to cancel my ticket, I was shocked to be charged a ₺2514 cancellation fee. My flight is almost a week away, and if I cancel now, they can sell the ticket to someone else immediately without any loss. Should I be upset about my visa not being approved or our national airline taking advantage of the situation by charging me a cancellation fee? I am seeking assistance from the authorities in this matter and request the cancellation to be processed free of charge. According to THY's information, cancellations and refunds made 12 hours or more before the flight do not incur any deductions.