LINE CANCELLATION

I send various e-mails to the cancellation dept to have a line cancelled. I receive one call to say they cannot as I need a letter from service provider(pc). Line is rented from Telkom but all else from Service provider for pc. I could not supply a letter as the company just release the line back to Telkom and they have never issued anyone with letters. After explaining this in another e mail(cancellations do not have a contact no). my e mail went unanswered and all other emails. Today is the 30th and I moved from that address and the line is still active. No cancellation was done by Telkom. So what now should I as customer just sit and wait for some one else to start using that active line and I pay the bill?Is this Telkom's way of making money? And line shoul have been cancelled today the 30th. 1Dec new owners move in