ATM CARD ****

My mom was ****** at an ATM by an unknown man. In a sense where someone pretended like he left his receipt on the machine then as my mom was about to insert her card the guy held her hand only to find that he was switching cards and the card that was inserted in the machine was not hers and it blocked. So somehow he saw her pin and went to withdraw an amount total to R6000 without her knowing. She called and stopped her card then went to an Absa branch at Mabopane central city. We thought they would investigate the matter and see that it was really a **** and that they would refund her, her money. But the lady who helped her said the money is gone is gone and there is nothing they can do. So my question is that, is it true that they can't do anything to help her get her money back. Because apparently some banks loom into the matter and give their clients their money back. Why can't Absa investigate and give my mom her money back. She is a pensioner and the money that was ****** was for my sisters tertiary fees. Please help me to find out from Absa bank if they can't do anything.