Cancelled landline

I phoned Telkom call center the 27th of July 2015 to cancel my landline with the reference number ***a.<br> <br> I received an invoice the weekend and I have been charged upto the 24 September 2015.<br> <br> However this is then 54 day notice and not 30.I phoned the call center and the line hasn't been cancelled and still active.I have already made this payment but need the line cancelled and the my LTE contract credited with this amount.<br>