Time for cancellation

I have sold my house and in the meantime I know that the new owner will move in in 2 weeks time. So far so good, but Telkom says I have to cancel my telephone 30 days in advance.<br> I told them that this triggers a problem - not for the monthly fee - but the new owner will be able to make calls on my account, and they are from overseas. <br> In this case Telkom charge me for calls, the next owner will make.<br> I had the idea to move instead of a cancellation, but it is the same 30 days. <br> I said, I will cut the line, so they can't use the telephone, but Telkom woud charge me for damages.<br> And they can't stop the service only, what would e enough.<br> What can I do ? My ISP for the ADSL stops immediately, but this is a private customer focused company.<br> It would be nice if the audience has any ideas