Avis did not pay back my deposit after a month

Avis my depsit of R3000 has still not been paid back since 17 April and today is 17 May..... this is unacceptable. I would not recommend using Avis. I returned the rental to King shaka KZN brnch but still no deposit.....please explain. How do I get my deposit back? Apologies and explanations did not pay my deposit back.