Bad credit due to Telkom's incorrect debit deducting

Since last year September I have been experiencing a problem with my Telkom account. Telkom has continuously deducted the incorrect amount (LESS THAN MY ACCOUNT) from my bank, and due to deducting less my account has accumulated in arrears.

Each time, when I call the Call Center I'm informed to make a manual payment and the problem will be fixed. THIS HAS NOT HAPPENED. October 2017, November 2017 and December 2017 I did that, but still my account is messed up.

I have been on the phone today since 08:00 this morning, with various departments, and just get sent from pillar to post and no-one can fix my account. Although it is Telkom that is making the mistake, I am penalized for this, and MY credit looks bad. I have logged many complaints and begged and pleaded many times and still NO resolve. Always the same answer, make a manual payment and it will be corrected, but I now refuse to do this anymore as it has proven futile.

They keep handing me over and suspending me due to their own faulty accounting. I've had to buy a pay-as-you-go sim for my phones and computer, just to do my work even thought I opted for a contract I cannot use. This is an extra charge, that I had to carry, due to Telkom's fault!! I'm exhausted, frustrated and tired of these complications that have been left at my door.

Can anyone help me, as the call center only send's emails and I don't think that the accounting actually understand the requests. I've tried to get a number or email address for the Account Dept, and politely get told that only they (the call center) is allowed to have direct contact with them.