Charge for service they knowingly do not provide

I have had a tracker in my car since 2011. Today I phoned to test the unit as advised by a friend of mine. The person in the call center told me that a test in 2012 was unsuccessful and it has not been fixed since then! He said I would have received an email informing me of the failure but I have no record of this and have only received invoices since 2012.<br> <br> Tracker is acting extremely *********ly by continuing to charge for a service which it knows it is not providing. Tracker has not made a reasonable effort to remedy the situation - no phone calls, no sms, no emails, no post or any attempt to inform the customer. As Tracker have willingly and knowingly failed to provide the service charged for, please refund me all payments made since 2012.<br>