Vodacom terrible service

Vodacom calls me to advise the contract amount is decreasing but they dont mention the once off admin fee to pay before it decreases! Then you have the nerve to debit my account with the additional fees! I then reverse it as I did not authorize it only for you to tell me I'm now liable for the reversal penalty!!! Absolutely ridiculous!!! To top it off I cant cancel the contract because of this outstanding balance!! you guys are the pits!!!