AVIS have still not refunded my holding fee.

RE: Rental Agreement Number : ***

Good day,

Please assist with a query regarding a rental I took on 23rd October and returned it on 31st Oct, I still have not received my holding fee after AVIS has charged me an amount of R2181.92 and I have not received my holding fee to date. I phone the call centre on numerous occassions and it is becoming frustrating.