False pretence

I was contacted by onair tv, the agent told me that I will enjoy all benefits of DSTV explora 3(the latest model) has to offer. When the installer came to install he made me aware that the price I was told that I will pay excludes the benefits I will still have additional cost that I will have to pay towards Multichoice. When I want to cancel I was told the decoder has been administed and that I will be responsible for the full term of the contract and