I've had similar instances when using foreign cards in the US. The charge will appear on the card as reserved, but it will not post as a charge to the account. After it expires (my bank after 1 month) the charge will disappear.

There is, of course, the possibility that your situation is different, but it is if you follow the steps Oliver2002 said, and they look up on the first segment you tried to book and you're not on that flight, then it's more likely the situation above.

Good luck.