Cancellation not processed?

I submitted written notice to Tracker of my intent to cancel my services with effect 31 July 2015. I have also spoken to consultants at Tracker where I notified them of my intention to cancel my services. I was given verbal confirmation that my cancellation will take effect 31 July 2015.<br> <br> Today I receive an SMS from Tracker telling me to phone them and that Tracker will continue to bill me for services (which I am not receiving, might I add...). When I call the number provided, a voice prompt notifies me that the number is not available.<br> <br> Tracker has managed to create frustration in every dealing that I have had with them from quotation stage to service delivery to cancellation. Stay away from Tracker.