Otelz.com Double Charge For Sofitel Booking - Refund Not Paid

I made a hotel reservation for Sofitel in Istanbul through the otelz.com website for a stay on January 28, 2026. During the payment step, the site showed an error message and asked me to try again. When I tried again, otelz took the payment twice from my credit card, even though the website reported an error. I noticed the double charge immediately and contacted otelz right away. They acknowledged that they had taken the money, but despite this, they have not refunded the extra payment. More than a month has now passed since the incident, and the additional 850 USD that was charged to my card still has not been returned. I have tried to reach otelz customer service many times regarding this issue. However, my calls were repeatedly terminated and they hung up on me, and I have not been provided with any solution or clear information about when my refund will be processed. I request that the extra 850 USD that was wrongly charged to my card be refunded to me immediately and that this issue be resolved without any further delay.