I want an emediate cancellation!

On the 19th of oct 2015 I called and requested and prepaid conversion on my number ***, the contract had to be cancelled by the end of that month however a ********** upgrade was done is sent all relevant documents to have an investigation done.. it took them the whole month when they had promised 14 days, now they have reversed the ********** upgrade but I demand an emediate conversion to pay as u go to avoid ***** being done again because of having to wait a few days before they can cancel the contract I want to have it done now and I want the money billed for this current month to be refunded coz my initial contract expI red in Oct and i did give notice in due time.