Money not reversed into my bank account

I rented a car on the 20th of February 2016 in Kimberley. I returned it same day within 2hrs in Bloemfontein. I was suppose to have been charged R679.59 but a total of R2328 was taken from my account. I was told that the R1864 will be returned after 7 days since its withheld by Avis. Today I expected my money back and it has not being reversed. I phoned Avis Kimberley they said that the money shows that its reversed on the Avis system but its not reflecting on in my account. Would you please reverse my money?