breach of contract

I took a motor vehicle insurance with Dot sure. I was told about a device that needed to be installed in my car for my driving behaviour.however I decided not to continue with dotsure. To my surprise I'm told I owe R497. 00 for the installed device and when I called Netstar I was puzzled that I'm in a 36 months contract with dot sure. I sent an email to the consultant that assisted me asking for a recording because I know the contract term was never disclosed. I need a recording from when I took my policy. I specifically mentioned that I had a tracker already but was told it goes with the policy and when I cancel they will deactivate the device.this is very dissapointing