Bad experience

This is the second time I am coming to this platform for help. I wrote a review about the above mentioned company late December, about a home router that I took from them. I did express that the router did not serve me be they continued to bill me every month. The matter is still continuing after several communication with them. This has affected my credit score in a bad way. They are still deducting even though I have tried to stop the debit order from my bank. I don't know what to do. They collected their router but still billing me. What is going on here.