Theft from account

Hi. SOme time ago my mom who is a pensioner with no cellphone and internet access had almost R3000 taken from her acount following a phone call from Nedbank about some Greenbacks thing. It was a **** but her call records show the number came from Nedbank it's self. She does not have access to her own transport and this makes it difficult to get to the branch and police station. Again today she went to the ATM only to find out that ALL her money has been removed from her account. She received no sms alerts about this. She is left pennyless without even money to buy a loaf of bread.