Lost R8500 via an EFT transaction.

Made a EFT from ABSA to Standard Bank on the 21th of May and the money was never received by the Account holder of Standard.Tried to phone the ********** 600 call centre and after being put on hold for 20minutes I put the phone down.the operator never came back in that 20 minutes.I tried again,the same happened,this time she came back just to tell me there was an Error with the Debit order "Debit not allowed" whatever that means.Now where is my R8500.?Can someone please help me get that money back please?