No Service. No-one to assist

We approached Telkom on 5 April 2019 to cancel 2 telephone line on 4 May 2019. They cancelled the one, but not the other. Called their call centre yesterday. Was told to send an email to the Assurance Cancellation Team, who will assist us. Received an email back from them to tell us to phone the Sales Department. The Sales Department has an automated system which then tells you to request cancellation online. When you request cancellation online , the system tells you that the cancellation has already been submitted. So basically you cannot speak to anybody about the reason for the cancellation not having taken place and nobody is available to sort the problem out. You have to pay an additional month's rental because Telkom cannot provide a service and who knows how long or if they will cancel the line.