Duplicate amounts deducted from account

I rented a vehicle from Woodford Car Hire on the 4th June, 2015 (Rental Agreement Receipt - PE-5178) to the value of R328.99. In addition, a fuel charge of R134.00 was deducted from my credit card a few days later, bringing the total cost of rental to R462.99, which was the total amount reflected on my credit card statement at the end of June.<br> <br> However, on the 6th July 2015, an additional amount of R134.00 was further deducted from my account. I believe that this amount was taken off in error, and promptly called the Woodford Car Hire branch at Port Elizabeth International. Without providing any explanation or apology for the inconvenience, they instructed me to email the Rental Agreement and a summary of the events as I understood it.<br> <br> On the 17th July I received an email from Woodford PE, informing me that there had been an error and that the issue would be rectified ASAP. To date however, the money is still outstanding and further emails have been met with silence. Please advise on how to proceed before I escalate this grievance directly with the bank, who have been informed that the money was deducted without authorisation. <br>