No cancellation done

I emailed Tracker on 2015/07/22 instructing them to cancel my contract as I had sold my car, I did not receive a response although I had used the correct email address, that I got from their email correspondence. When I called the call centre a few days later they confirmed that the email address was correct but could not tell me why I did not receive a response. I was then advised that I have to give 30 days notice before cancelling, I asked why they were insisting on a month's notice when I pay them in advance... dololo (no answer, again). The lady I spoke to said I would be contacted by the retention's department.. again dololo (no call received to date). In the meantime I have been debited for August as well as September.. I cannot reverse these debit orders as Tracker has somehow found their way into my credit report. If this isn't **************** then I am not sure what is..?