Ajet Denied Check-in and Unhelpful Staff

On 27 September I was booked on Ajet flight VF1987 from Istanbul to London Stansted and was denied check‑in at the airport. I had a valid booking and boarding pass for this flight, yet I was still not allowed to check in. At the airport I had to walk up and down between 8–9 different counters for about 2–3 hours and kept being sent from one place to another without any clear information or proper response. During this process the Ajet staff were very unhelpful and did not provide me with a clear or reasonable explanation for refusing my check‑in. They first told me that all flights for today were overbooked and that there were no available seats, but when I checked online I could clearly see that there was a seat on the 12:55 flight today. Even though I am now finally on a flight about four hours later, the staff continued to deny this availability at first and behaved in a very mean and misleading way. They even told me to go to a hotel and stay there, although I clearly explained that I have work tomorrow which I absolutely cannot miss, and despite this they kept giving incorrect and misleading information instead of helping me reach my destination on time. I was left in a very difficult situation as a result of this and was not given any proper assistance or alternative solution during those hours. I request a clear written explanation of why I was denied check‑in for flight VF1987, why I was misinformed about seat availability, and a suitable compensation for the inconvenience and damage caused by this incident.