Contract issue

I have been using vodacom network for more than 15 years but today I am so disappointed,with their service On contract I have canceled contract on two month ago instead of them canceling it they have increased amount,my problem this it will effect my credit score as I am no longer work so I dont know what I am going to do as I have been paying them until my contract end without missing any payment... This is it happening for the second time every time you have to finish contract term it's like they dont won't to see you finish it but they want to keep you as their slaves for the rest of your life for me to get peace I think I have to choose another Network provider and leave this trash.