refund issue - Consumer Complaint for AVIS RENT A CAR - HEAD OFFICE

I haven't received my refundable deposit of R2880 back into my account its been more than a month now. The car was returned back to avis on the 3rd of August in time and undamaged, I have sent many emails to customer service and called avis several times I was told to send an email I have done that but still I haven't been helped. This whole thing of avis not returning my money back into my account is now frustrating me and I have checked with my bank (std bank)there's no money that was ever released back into my account I really don't understand why is avis doing this to clients its unethical.