Sunexpress Flight Delay Ruins My Vacation Plans - Seeking Compensation

On July 01, 2024, at 07:55, I had a Sunexpress flight XQ300, with T8TB2M and hadxua PNR codes, from Antalya to Cyprus. Our flight was delayed by 12 hours on the first attempt (until 20:00) and 3.5 hours on the second attempt (until 23:30). The plane took off around 01:10 on July 02, 2024. By the time we landed in Cyprus, it was 02:00.
Despite Sunexpress staff repeatedly insisting that we were entitled to ₺250 compensation per passenger from the morning hours until the actual departure time, they now claim we have no right to compensation. The crew told us multiple times that we were entitled to compensation and even gave us forms before the flight.
Our meticulously planned vacation, for which we had taken annual leave months in advance, was ruined. We couldn't even enjoy one day of the hotel we had paid for, and our entire trip was a disaster. It seems Sunexpress misled us about our compensation rights to avoid backlash, only to dismiss our claims after the flight.
I have submitted an application to Sunexpress regarding this matter, but they are brushing it off with a response like "We regret the flight disruption you experienced. We cannot evaluate your request positively as you are not entitled to compensation under the delayed flight rights regulation." I would like to inform you that I will also take this matter to court.