What is the issue? You placed an order on a friday night, the store processed your credit card as it is most likely set up that way through their payment gateway and come Monday evening, they tell you it's not in stock. Not sure what you do for a living, but not all of us work 24/7 or own a business that is staffed 24/7
It looks like they handled it just fine. I've never dealt with them, but at least give them a fair shot