Possible cancellation of contract

There is a possibility that I want to cancel one of my contracts with Telkom. I contacted the Telkom via email to get the amount should I wish to cancel. I was first told to visit my nearest branch. The branch in our town closed, which means its quite a distance to travel to the next nearest branch. I asked them to give me an estimated amount then via email. Apparently I cannot be given an amount to the number in question as that line is suspended. This is due to a ****** device which Telkom, after a dispute, refuses to replace. I've decided to leave this matter but might want to cancel the contract then rather. So the sim was cancelled with the ****** device and thus the account is suspended but I still pay each month regardless. So I questioned the amount on the other number also with Telkom, which they still cannot provide me with an amount as it is linked to the same id nr as the suspended one. I feel this is Telkom refusing to help me as they don't want contracts to be cancelled and one must still pay each month as they do not want to assist you. So I need to travel about 30 kilos to my nearest branch and back home again just to get an answer that they cannot help.