Contract cancellation

Accelerit gave me the worst service ever, network down most of the time, when I call them they transfer my call until they hang up.I canceled my contract with them in writing, logged a ticket in September 2022, logged a ticket for cancelation, served a 1 month calendar notice and they are still refusing to cancel my contract, which I have been with them for almost 2 years now.I tried sending emails, calling and they are still debiting from my account even though I am not using their service anymore.