Duplicate charge

Good day All, on the 11th March 2024 i experienced a duplicate charge at the petrol station Engen Garage 14th Avenue in Roodepoort. The cashier advised me that the refund will happen after 3-5 hours until now nothing has happened and my money hasnt been refunded. The Engen Garage manager logged a call with FNB stowe group whom they are not responding to emails until today. I need my money as urgent as yesterday, im tired of waiting. Can FNB REFUND MY MONEY PLEASE.