Turkcell Marked My Paid Bill as Unpaid and Customer Service Did Nothing

I am currently facing an issue with Turkcell, as my paid bill is still showing as unpaid because of their malfunctioning system. This situation is incredibly frustrating as I have clear proof of payment, but their system just won't recognize it. I reached out to customer service several times, but they were not helpful and seemed to lack the expertise needed to offer a genuine solution. It seems like I'm communicating with an unresponsive entity instead of a business that truly cares about its clients. Rather than addressing the problem, they continue to send me unclear replies. Their old system and absence of responsibility have made me feel powerless. I’m not looking for a favor; I just want the problem resolved. If this is their approach to payments, I shudder to think about how they would manage more critical issues.