Superonline Charged Me for a Modem I Was Ready to Return

My Superonline home internet contract has ended, and I have no outstanding debt. I made my final payment on July 14, 2025. Despite this, I am being charged ₺1,073 for a modem. Although I still have the modem and have committed to returning it, I was given no clear instructions on where or how to return it. Initially, I was told that they would collect the modem, but they later went back on their word. Even though I’ve paid all my dues and am willing to return the modem, an arbitrary fee is being imposed on me. I receive conflicting answers every time I speak to customer service and am tired of repeatedly calling them, so I’ve stopped. My grievance has been ongoing for about a month. I have not paid the ₺1,073 charge because I believe it’s unjust. I request that this unnecessary charge be removed and that I receive clear instructions on how to return the modem.