Holding deposit not released after 23 days

I rented a vehicle on the 26 April 2019 until 29 April 2019 there was a holding deposit on my FNB cheque card of R4000 the transactoon was closed and today is the 22 May 2019 and im still waiting for the authorization to be lifted. I have made several calls then on the email from customer service they informed me on the 17 May 2019 I have to wait 2 business days. What is happening