Deposit refund

I rented a car from Avis Randburg & have since returned it. On the 3 March my cheque account was debited by Avis, an amount of R420. I called their call centre and spoke to Mando, ref *** who assured me that my deposit, R1500 will be released and refunded in 48hours. 3 days later and I am still waiting for my refund.