Cancellation confirmed by Telkom, but not actually done.

Cancellation confirmed by Telkom, but not actually done. My husband cancelled our Telkom line in December and received the confirmation emails. For some reason, the account is still open and they are still charging us every month. We have called and emailed, received further cancellation confirmation emails but they keep on charging us. This is unacceptable, we need this sorted out and our money paid back immediately. This amounts to *****