Paying for service never used.

I have recently got aware that I have been paying for the Blackberry internet service for more than three years. I have been debited about R51.00 for three years and when I want my money back they say I should have phone them to cancel the services of which I was not informed when I took the contract three years ago.

The contract for blackberry has expired two years ago and I was not told to cancel the BIS.

The last time I log a query the Vodacom consultant was very rude with me and he said its my own problem that I did not phone to cancel the service.