arrangement not noted

An amount of over R4000 was requested by an overseas company, I did not have any funds available on my account at that time, 20/01/15. But Absa went ahead and honoured the amount without confirming with me even though I have not authorised the transaction nor have I ever shopped online nor from an overseas company. This transaction reflects bad on my credit record because my account is now over line. I have disputed the transaction, they referred me to ***** who then referred me back to the merchant. Absa contacted me wrt the arrears amount and I explained the situation to them, also informing them that I will pay as soon as I have the money. Now they went and take R1711 from my bank account. I want that money back, and I will pay before the due date.