Am having some issues with the AA booking site. If I enter origin and destination everything works fine. However, if I use the multi-city function for the same routing (e.g. in order to choose a particular connecting airport), the site seems to work fine and offers me various options (at the normal prices), but once passenger details are entered and confirmed, I get an alert saying that the fare is no longer available. I tried dozens of different routings/options, always get the same error message. Is this a known issue with AA multi-city bookings?