A week ago I tried booking a multi-city SEA-PHL, overnight stay and PHL to YHZ in first class. When I tried to actually book, I received the "Choose a different flight or fareWe're sorry but at least one of the flights or fares you chose is no longer available." message.

I booked the first leg in first and the second in coach for a fare that was about $70 less than what I wanted to buy. A day later the original fare still showed on the AA website so I called the EP desk and was told that a fare may be offered but not actually available, even though the second leg is showing 4 seats available at the quoted price.

Even today the same fare shows on the AA website but gives the error message when you try to book it. The second flight is only 2 hours and does not have meal service in first, so it's not a big deal. Nevertheless it is frustrating the the fare I wanted is still showing on AA's website but not actually available.