Vodacom the worst!!!

I have been trying to cancel the fiber at my old address since end of November last year with no success and I am still being charged for a service I am no longer receiving. We had to move as the house we had the fiber at we were in the process of buying and after a year it was still not registered so we canceled the deal & the owner wanted us out so bought somewhere else, unfortunately we could not move the fiber with us as there is no fiber here at my new address! Please could someone help me sort this out asap, as I shouldn't still be paying for a service I can no longer use! Vodacom is still debiting my account since the end of November but I feel I should no longer be paying anymore.