Contract Cancellation still undone!

I am highly irritated with the fact that my contract has still not been cancelled. I have completed the Consumer Request for Cancellation form on the 06 October 2015 for the following number ending 1920 - And My contract has still not been cancelled and I have been billed for it. You guys need to refund me and cancel the contract ASAP. I went to the branch yesterday and an agent logged a ticket for it to be attended and now no one has contacted me yet. I have phoned 10210 and the lady who answered my call told me to phone 10213 but I have been on the line for 15 minutes and not a single person has picked my call. Solve this ASAP my case number is: ***9