Cartrack installation problem and the length of the contract.

I have entered a contract with Cartrack over a year ago. The contract was discussed on the phone, the installetion was done, after. A week I realized that my reverse camera was not working anymore. I phoned Cartrack and told them about the problem, that it occurred after the installation, they did not respond or came up with a sulution. I awaited nothing happened,. I phoned again and said that I want to cancel the contract, the lady on the phone said that I could not do this, I told her about the reverse camera that was not working after the installation. This she blantly ignored, told me that they would black list me. I originally believed that I signed up for a two year contract, just to find out that it is a three year contract. No where on the document that I signed after the installation is there any indication of the length of the contract. My personal feeling is that Cartrack does not care about its customers, this is very poor.