Turkish Airlines Misinformation and 16-Hour Airport Ordeal

I purchased a ticket for the Turkish Airlines 10 AM flight from Istanbul to Ankara. My ticket indicated gate number G1, and we were asked to wait there. Despite the scheduled time, the gate remained closed, and when we inquired, we were told that the gate had changed, and the flight had departed. My family and I had to wait at the airport from 10:00 AM until 2:00 AM the next day. This experience caused both psychological and financial distress due to the unexpected delay. THY provided a ticket for the 2:00 AM flight, claiming to resolve the issue. However, their actions led to additional expenses for meals at the airport and missing an important event in Ankara. I am deeply dissatisfied and need to express my complaint.