Seat Reservation Issue of Turkish Airlines

THY misleads its passengers by offering 'seat reservations' for a fee before check-in, but it's all an illusion. Here's what happened: I instructed the agency to purchase seats for our return flight with my spouse using PNR v n d h z c. The agency confirmed that they sold us seats 12J and 12K on the relevant flight. Attached is the invoice dated October 10 for my spouse's seat issued by THY. Notice that it doesn't specify what was sold; we paid, but it's unclear what we received. When we logged into the THY site to check-in online 23 hours before the flight, we saw that my spouse's seat number was changed to 27A, 15 rows behind mine. Our agency contacted THY customer service, which first claimed 'You made the wrong reservation' and then 'Submit a written application!' followed by 'We will listen to your reservation's voice recordings.' After 10 hours of struggle, THY admitted it was a 'staff error' and reassigned seat 12H next to mine for an additional fee. From a brief conversation, it was clear that the passenger who took my spouse's 12K seat was someone privileged from the airline community. One should not purchase seats from an airline that operates this way! After the mistake, I requested a refund for the reallocated seat for my spouse, recorded under number TK-9702327, but no response has been received via email.