Incorrect billing for 9 months now

I have a Telkom account for 9 months now i have logged several disputes in regards to incorrect billing the last time the dispute was logged 05-10-2017 i got a call saying that i will be credited the amount that i over paid and it will be right going forward,i received the credit but i am still being billed incorrectly,see dispute ref ********** 2 for my account and comments in description for better clarification to ongoing issue.