Continued debut order after cancellation

I cancelled my insurance last year September when I dropped my phone and they refused my claim. I have been charged for this insurance every month since. I spoke to a consultant who told me it was clear on the system that I cancelled in September. When I have eventually managed to get a hold of the insurance department they suddenly have no record of my cancelling. Seems like just another example of poor customer service by a company that *****s from their customers.