Frustrated by SunExpress Due to Incomplete Refund

I bought an international ticket with the number 5642160131*** for 12,600 TL, but when I canceled it, I only got a refund of 880 TL. They said the ticket was bought from a company called Obilet. I'm really let down by SunExpress and Obilet. I feel like I trusted the wrong person, and I'm not going to ignore this. I'm ready to take legal action if I have to. This situation has made me not only financially inconvenienced but also frustrated because both parties involved are not clear and responsible. It's really discouraging to have to go to court, but I think it's the only way to make sure we get a fair solution to this problem and make these companies take responsibility for what they did.