Car rental deposit not being refunded

I took out the courtesy car from AVIS on the 3 September 2015. I paid a deposit of R1200 at the Francis Baard branch using my Standard bank cheque. The courtesy car was returned to AVIS on the 1 October 2015. On the 2nd October I visited the Francis Baard branch and was told that the deposit will be reversed back to my account within 7days. On the 9th October an amount of R125.40 was debited by AVIS from my cheque account. On the 12th October 2015, I visited the Francis baard branch again and was told that it was the money for the E-tolls. When I enquired about the deposit, I was told that there was a hold from Standard Bank and they will send a message to STD bank to release the amount. On the 15th Oct, I called AVIS and was told that they received a confirmation from STD bank that there is no pending authorization from them. When calling STD bank, they are not picking up any reversal from AVIS. I called AVIS again and they are insisting they that the problem is with STD and STD bank blames AVIS. Can STD bank and AVIS sort out their mess and reverse back the money into my account.