Line still not disconnected after almost 9 months

In August 2015 I cancelled a line from a property that I had sold and moved out of. A new line was allocated to the new property. Despite going into the branch numerous times, receiving copies of the cancellation forms, and even a phone call from Centurion branch to say it will be done by end March 2016 (the latest), I am still being billed for this account! <br> Find this absolutely unacceptable. Firstly you sit for almost an hour to get helped by a consultant, they promise the problem will be rectified - the costs reversed, and the line cancelled - but still NOTHING!!!