Turkcell Superonline Fiber Internet Constant Disconnection and Slow Speed

I have been using Turkcell Superonline fiber internet service for a long time at my address. However, I have been experiencing constant disconnections and low-speed issues for years. These problems occur continuously throughout the day. I have contacted customer service multiple times, but each time, I was dismissed with different excuses, and no permanent solution was provided. Instead of resolving my issues, I was repeatedly told to upgrade my package and pay more, yet nothing improved. I have also been submitting complaints for years, but I only receive automated responses saying, “your complaint is under review,” without any real action taken. My problem, instead of being solved, has only gotten worse. My subscriber number is 51087540. Due to this ongoing inconvenience, I request either a permanent resolution to the issue or a refund for the service I have been paying for without receiving proper quality, along with the cancellation of my subscription.