Stuck with Avis long after the car is returned

Hired a luxury car from Avis five days ago - for one day. Returned the vehicle the same day. Avis reserved the ENTIRE excess of R90'000 - that's right, R90k on my credit card.

It's now five days after I returned the and the excess is still not reversed, so I can't use my credit card because it's maxed out. I deliberately set a smaller limit in the event of *****. Never anticipated a rental company reserving an amount of R90k

And even if they did, at least release it when I returned their vehicle in one piece.

Rental confirmation no: 2235 382