Tuesday 17th -- Tried to book three-legged trip. Signed in with OP number, chose the flights, clicked "Purchase," screen comes up, Traveler 1 with all information correct, I click "Continue" and the same screen comes up (personal information) with the caveat:

! We could not process your request. Please see the message below and make revisions.

But no message below!

If I hit "Seat Selector" (the other botton at the bottom) it just takes me back to the "Traveler Information" screen, with no seat selection possible.

So, stuck, no purchase possible. Any idea why?