Pegasus Airlines Denies My Rightful Ticket Cancelation Refund

I purchased a plane ticket from Pegasus Airlines through enuygun.com on January 19, 2024, to travel from Gaziantep to Cyprus on Thursday, January 24, 2024. Along with my ticket, I also paid an extra fee of ₺251.49 for a priority service package, which promised a 90% refund in case of any issues (ticket protection). Additionally, there's a service fee of ₺56.99 listed on the invoice. On January 23, due to unforeseen circumstances, I needed to cancel my ticket and purchase a new one dated January 23, 2024. However, neither Pegasus nor Enuygun.com's systems allowed for this change. I contacted both companies' customer representatives, but they simply passed the buck, saying that the 90% refund only applies to a portion of the ticket price, not the full amount, which totaled ₺1668. They also claimed that there were no service fees, which I wasn't informed about.