The charge you see could be any one of the following:
A pre-authorisation is just a validity check that temporarily blocks on your credit card an amount roughly equivalent to the cost of your reservation. The amount will be unblocked after a certain time period. How long this takes will depend on the property and your credit card provider.
Deposit or Prepayment:
Some properties require a deposit or prepayment at the time of reservation. This policy is clearly highlighted during the reservation process, and you can see it in your confirmation email as well. If you are eligible for free cancellation, this amount is returned to you if you choose to cancel your reservation.
If you feel you have been charged in error, our Customer Service team is happy to find the best possible solution for you. Please contact us with your reservation number and details of the charge made, and we will follow up on your behalf.