Turkish Airlines Changed My Seat Despite I Selected Paid Seat

On April 19, 2024, at 18:00, I had a flight from Istanbul Airport to Ankara with my mother and my 4.5-year-old daughter. 24 hours before the flight, during online check-in, the plane showed 2 seats on each side and 4 seats in the middle. Since I didn't want to sit in the middle, I paid for a seat change. Although we wanted to sit together, we chose 2 seats on the side (33A, 33B) and a window seat in the row ahead (32A) to avoid sitting in the middle. I paid ₺225. To avoid missing the check-in time, I selected 32A for my daughter, 33A for my mother, and 33B for myself, thinking we could easily swap seats. I printed our boarding passes. On the day of the flight, there was no announcement about any changes. Around 17:15, I asked a staff member about the flight and was told there would be two flights to Ankara at the same time, and the plane would have a 3-3 seating arrangement. Despite mentioning my paid seat selection, I was told my seat numbers would remain the same. However, I ended up in the middle seat of a 3-seat row, and my mother was seated in the front row, next to a stranger. Additionally, my seat was now at the very back of the plane, as the new plane had only up to 33 rows. I paid extra but did not get the seats I wanted (to avoid sitting in the middle and next to strangers) and had to sit at the back. THY's unannounced change could have resulted in a worse outcome. I had selected 32A for my daughter and 33A and 33B for my mother and myself. If I had chosen seats further back, my daughter might have been on a different flight. I request a refund of the ₺225 seat selection fee, as I did not receive the service I paid for (no one was seated next to the selected double seat).