Money disappeared from my 32 days savings account

On the 6 October 2015 R5301.50 disappeared from my 32 days notice savings account. I called *** four time every person I spoke to told me to hold until I ran out of airtime and no one getting back to me. The last person I spoke to(Trish) was very helpful, she called me back after my airtime ran out again. She told me the money was taken by standardbank at balfour park and they will call me before the end of the day, Received no call. On the 7 October 2015 went to standard bank at sunnypark. Godfrey said he doesn't know why they took the money, so he wrote them an email and told me that they will call me before the end of the day or tomorrow. Received no call again. So went back again today and he told me that they said I was given a wrong salary and since I used the salary that's why they took money from my savings account. How do people from the bank take money from our account without our acknowledgement and permission. I would like my money to be returned to my savings account please