Turkish Airlines Ticket Issue with In-flight Meal Charges

In October, I purchased a round-trip ticket from Turkish Airlines for a departure on May 18 and a return on May 26 at 12:35 PM from Vienna. I chose the ticket considering the meal and luggage weight allowances. I flew to Vienna with Turkish Airlines without any issues. However, on the return flight on May 26 at 12:35 PM, Turkish Airlines had changed the flight to Ajet. During the return flight with Ajet, I was asked to pay for the meal. I explained that I had already paid for it and would not pay again. The flight attendant, whose name starts with P****, stated that meals on Ajet are chargeable. They checked my ticket and acknowledged, 'You are right, you bought the ticket from Turkish Airlines, but the aircraft was changed.' I replied, 'This is not my problem, I will file a complaint.' The attendant shamelessly responded, 'Go ahead, sir, file a complaint.' I purchased my ticket from Turkish Airlines and paid for it. I am not the one who changed the aircraft. Even if you put me on another flight, you are obligated to provide the same service. I am filing a complaint against the flight attendant named P****, another male flight attendant whose name I did not get, and the Turkish Airlines management responsible for this issue. I request that appropriate action be taken against all personnel who caused me inconvenience.