Absa Idirect false debit order. no permission.

I have had my account debited with over R19,000 a few months ago. I had to take time off work to go find out at the bank what this was for. just to come find it was ABSA Idirect. apparently somebody re-opened my previous insurance account which was cancelled nearly a year ago. And on top of that, the amount was *****ed with as the old amount was R1,900 and somebody moved the comma and made it R19,000. absa did not want to tell me who did this or why? Eventually I had the money reversed and had the account at Idirect closed again. No again my account was debited and I had insufficient fund for the debit. This means it has been re-opened again. this will be the 3rd time. All the bank chargers remain to be at my cost. Absa Idirect is a real problem to me.