Those threads may be relevant but mrploddy needs to tell us the currency of the charges or at least whether the hotel is a US or non-US hotel.

In most or maybe all countries outside the US, prepaid Hilton stays are never charged at the time of booking.

They are charged when the reservations staff working at the actual hotel notice a new booking and then put the charge through their computer and/or card terminal. This can happen a few hours after booking, but it usually takes a day or two, occasionally shortly before check-in and sometimes not at all all - then you just pay on check-out.

If mrploddy's stay was outside the US, then it seems to be incompetent staff or a problem with the billing. This issue could arise if using something like the Curve card or the defunct Travelex Supercard, where authorisations actually post as charges to the underlying linked card, and the transactions are refunded when the authorisation is "released", but an Amex was used here so it shouldn't really happen.


Yes I understood all of that from the OP, but you said something about Amex denying that there was a problem. Well, I suppose from Amex's perspective you just stayed at a hotel 3 times.

If this happened to me, I'd just refuse to pay again at check-out, because as far as I'm concerned I have already paid. The hotel would then have to submit a cardholder not present transaction if they felt that they had not been paid; I would then dispute this with Amex.