I cancelled this service a year ago but it was still deducting every month

I am not happy about this service, I have cancelled this service long time ago, in-fact some time last year only to find out that I am still paying for it.

I tried to get hold of a manager but I was not put through, I could not get the managers number and I have been waiting for a call back for over a week now. I am really not happy about the service and lack of willingness to comply