Am dissaponted with Nedbank

HI, I have been with Nedbank for years now, but happened to me is unacceptable. Someone deposited R450 in to my account yesterday, I got a notification that R450 was deposited in my account, but to my surprise when I check the balance R300 was gone. I then downloaded a statement nothing was showing on what happened to the R300.This morning I called Nedbank customer care, an agent by the name of Nompumelelo Mbatha answered my call.She told me she can not see what happened to my money.So am asking myself who will be able to assist me if Nedbank agent cant help me?

I need answers : ***