I'm trying to book a flight on Thai Airways in December 2013 and I just noticed that a bunch of availability shows in different cabins on the flights that I'm looking for on united.com. However, when I call and speak to a UA agent they say that they can't see the space, let alone the flight at all. It's a multi segment trip, so I can't do it online.

What would be going on here? I don't see it on ANA tool either. Is this "real" availibility? Any way I can get it booked?