ATM

I last used my ABSA ATM card on 11 October to purchase takeaways. Yesterday, 21 September I got a SMS that R1000 had been withdrawn from my account. I checked my purse & the card is gone. I called & stopped the card. I then asked the ABSA representative how someone managed to use my card without the PIN. He told me that this is a puzzling thing to everyone at ABSA! This is unacceptable! I have been using this PIN for almost 20 years & it is not written down anywhere. How did someone manage to get my PIN more than a week after I last used my card? The only logical explanation is that someone at ABSA gave it to that person. Therefore I believe that ABSA is responsible for my loss & should therefore reimburse me that R1000.