FNB Just closes account .No Notify

I had someone sent EFT of R800 not aware FNB had closed my account..and now when i ask the sender to reverse the money they told me i have to take it up with FNB.so how do i get my money if FNB just goes about closing peoples bank account without any notification..is this a way to take our money because next they might not even be able to retrieve it..m so worried about this.