Impossible to Cancel

I phoned Tracker in June to cancel my subscription, they refused saying that I had to give a calendar months notice. They however sent me an email dated 19 June 2015 where they confirmed that I had cancelled. Now they are sending me an Invoice for August and informing me that they will subtract my debit order again. I phoned the call centre and was transferred nowhere and after holding for 30mins I called back. This time I was informed that it would go to a supervisor. I still haven't received any response.<br> <br> I will never use their service again and I would advise anyone out there against it.