Nedbank appalling IT Security

On the 31st of May (which was my payday) I woke up to my banking app not working I then thought it was a technical glitch. However, I later discovered that there is no money in my account. I then approached the bank where it was also confirmed that my mobile banking app does not work and that there is no money in my account. The bank discovered that my salary was transferred into my account but was later deducted by an unknown number. The bank has since told me that they will investigate this matter and come back to me. They have also promised to re-activate my app which has since not happened. It is now the 6th of June and I have still not received any update regarding the investigation, I am unable to settle any bills or make ends meet for my family. I am left stranded not knowing what is happening with no communication from the bank. I am so frustrated , I have bills to pay.