Ewallet query

Today at around 09h58 am I have made an ewallet to my sister for R500 then within second another transaction of R500 and it was not me by technical error then within a second all those 2 R500 were reserved but it was not available in my account and my sister was unable to withdraw the money. I have tried calling *** for 2 hours with no luck then I went to fnb at PONGOLA and they have told me that they cant assist me even though the saw my statement doesn't add up .They told me that I must call *** and I have told them that I have already called that number with no luck so meaning now I have lost R1000.i have also send some email with no response.