Turkcell Charged Me Unjust Late Fee After Renewing My Contract

I am a Turkcell subscriber. I signed up for a one-year subscription between 25.08.2023 and 25.08.2024 at a discounted rate of ₺152. On 01.08.2024, I was contacted by Turkcell and informed that my contract had expired and needed to be renewed. I renewed it at a rate of ₺280. However, 15 days later, I ported my line from Turkcell to Vodafone, and Turkcell charged me a late fee of ₺2,900. This is completely unjust and unfair to me, and I am filing a complaint. I expect this mistake to be corrected.