I don't know why I keep using Telkom!

Telkom phoned me to offer me a Vuma 20mb/s, which I accepted. Now, I did ask whether the 30 day notice applies as I'm a current Telkom contract holder, which I was assured doesn't apply as I'm moving contracts within the organisation as per the offer. The fibre was installed the weekend afer the offer, the router was only delivered 5 months later. I communicated, and notified Telkom that the fibre is now activated and they should please cancel the ADSL that I'm currently on, yet when I received my bill, I was charged for the Fibre and the ADSL! Also, to top it off, I'm bein charged R800 for fibre that's only 10mb/s and not 20mb/s as advertised! is this how Telkom does business!?