Funds gone missing from saving account!

Im a account holder at nedbank an amount of close to R5000 went missing from a saving account (my pocket). To my suprise the poor service i recieved they say i must wait for 24hours before they can see where that amount has went. Mind you its month end i have to provide for my family. Whats the use of having a bank account if your funds will go missing then the explination you get is that they also do not know!!