Debit order amount still too high after SIX MONTHS

I changed my internet subscription contract in May, and am still being debited by an amount far higher than my contract stipulates. I can understand if this happened once, mistakes happen, but the branch I have been dealing with has queried this many, many times and has had no success in changing it. This is NOT the branch's fault. I have seen the reference numbers they keep getting and have stood there each time they have queried it. We finally managed to get acknowledgement of the error last month, yet the same amount has been taken again. <br> I have tried the call centre myself, and have received a different explanation as to why this is happening each time. <br> Nevermind the fact that each bounced debit order costs R150 in bank costs! I have also not received an actual account statement since a month after the issues started, so it's now guesswork as to what will be coming off my account.