SunExpress Demanded 20 GBP for Check-in

I am absolutely furious with SunExpress! This is truly a ridiculous experience. Last week, we waited two hours for our luggage. Today, we arrived at Terminal 2 in Antalya to fly again, and because of a system error on their online platform, we couldn't complete online check-in.

When we finally got to the desk, the completely uncommunicative agent demanded 20 GBP (approximately ₺800)! I had a screenshot of the online error, but she ignored it and still tried to block my flight. When I tried to explain my problem at another desk, they just sent me back and forth like a ping-pong ball. Only when I raised my voice a bit was my check-in finally completed. Even their supervisor doesn't seem to know what's going on.

SunExpress, you need to fix your online check-in system and stop these outrageous fees! This kind of arbitrary charge and abysmal customer service are unacceptable. Refund my 20 GBP now and train your staff properly!