Impossible to cancel a vodacom account

I'm trying to cancel one of my accounts due to the fact that I'm not using it. But cannot get hold of the cancellation department. Sitting on a call for 20min waiting for someone to answer then when they answer the call gets dropped and the whole process starts all over again. I have been trying multiple times now. I'm at the point now where I'm going to cancel al my contracts with vodacom. How do you go about cancelling a contract with vodacom