Upgraded Contract still being charged for the prev

I upgraded my contract in the beginning of August 2015 and i was specifically told by the sales consultant that I will be paying the new rate - R205.00 as of September 2015. Cell C took a debit order amount for R458.00 which is the old rate for September 2015. I queried and was told I will be billed for the old phone until November 2015 as this is my contract period. The new charges will be effective as of November 2015. I would not haven taken this phone had i known this would be the circumstance as i am not getting the minutes talktime i was for my old phone, but i am being charged the same price.