FNB pay me back my money please!!!!

I am frustrated and so disappointed by FNB. Money was deposited into a incorrect account by mistake and the acc holder advised us to reverse it,R2500.00 to be exact towards rent, we immedietley rushed to the the branch but was advised that we couldnt get assistance and need to call the call centre, i called same day and was told it was a ********** acc which had several cases linked to it, my question to the bank was, why is the account still active if its a ********** account linked to many other ***** cases, This was in October its Feb now, the investigator tells me to get an affidavit, proof of payment an the conversation between myself and the acc holder,which i did. Now he says get a case number, the SAPS advised that they can only open a ***** case if someone is suspected of ***** and they need the acc details of the acc holder to make arrests since an ID and finger prints were used to open the bank acc and if this is linked why did they keep it open and not on high alert??Good question i also think. Now the investigator is telling me the SAPS can get a supena for the acc holder details. All this for R2500.00 i mean really FNB????4 months me running up and down to the bank.saps, making endless calls and sending emails for my money but no one can assist or get back to me.I asked for a recon the same day i called to reverse the money which they can do but NO they couldnt do that either.Having worked there before i know how these things work and honestly im disgusted that my problem has not been sorted out yet!!!Please pay me back my money i need it