Telkom Bad Service

I have recently moved from one suburb to another and requested my line to be moved. After 3 appointments I eventually got hold of the technician who told me that there is a cable fault but he could not tell me when this will be fixed. I pay by debit order every month for a service I don't have. How can i go about cancelling my Telkom line? Is it contract driven? Or can i cancel at any time? Do not also want to be black listed for not paying something, but can also not pay for a service that i don't have!!!!!!