Car hire reservation cr card authorisation

On the 10/12/17 hired a car from tempest george airport through international online car hire agent,and received bank notification that amount of R7200 has been reserved showing reduced cr balance by such amount.fine. On internet banking no amount pending reflected.fine. On3rd Jan followed up with a query from merchant that was attended by Debbie Christmas from car hire-tempest Europcar- and she immediately mailed to bank at -cancellations@fnb co.za -requesting the funds to be released to customer and CC'd me on mail.still nothing shows on account. Then 24 hrs later called cr Card department for explanation,consulted with Lindiwe on phone correspondence and she told me about dr and cr reflecting on account amounting to +-1200 for car hire dr on credit card.fine but nothing about the money served for insurance purposes. And today went to mosselbay branch,called cr department,still no resolution about reserved amount to my understanding,went to car hire merchant at george airport and was told that the money unreserved suppose to show positive on balance as when reserved reduced balance. And today spoke to itumeleng from credit card authorisation,and she cut me short due to system technical pros and promised to call me back as when unreserved should show positive on balance.waited till 30 mins passed and recalled.still she told me she can only see dr amount for hire on system with no explanation of what happened to reserved funds. And right now feel absolutely mentally paralyzed. How come the bank notifies me for reserved funds showing reduced balance and can't return to positive balance when unreserved.