Problems with Flight Reschedules and Financial Loss on Pegasus Airlines

My Pegasus Airlines flight with PNR: JP65AU from Mula-Milas Bodrum Airport to Ankara/Esenboga could not take off on September 20th, 2023, due to the airline's mishandling. As evidenced by the attached document, on August 31, 2023, I changed my flight, which was originally scheduled for September 20, to a new date, September 23, 2023. However, I was unable to complete the online check-in, so on September 19th, 2023, at 09:52, I called a customer representative who confirmed that I could do the check-in at the airport. Based on this information, I arrived at the airport at 20:00 on September 20th, 2023, only to be told that my name wasn't on the flight list and that I wouldn't be allowed on the plane. Even after I spoke with Pegasus customer service at 20:19, they assured me that the flight change had been documented and that there should be no problems. This was confirmed by the entire Pegasus staff at the airport. However, the Pegasus ticket counter employee in Milas/Bodrum insisted that they send an email to their relevant department for ticket reissue and that if they didn't hear back, I wouldn't be able to board the flight. As a public servant with work obligations the next day, I was forced to purchase a new ticket for the same flight, PNR: M7X8VT. I am now requesting a refund for the second ticket I had to purchase as a result of Pegasus Airlines' confusion and delays.