Just a trap for young players.
Yesterday I booked a domestic flight in the US on the Australian website.I kept getting an error message when I put my husbands birthdate as mm/dd/yyyy ( as per the instructions ) but of course not the usual format in Aus. Eventually I rang United and got put through to web support who said "oh try putting in dd/mm/yyyy (as we always do in Aus) . I did this and voila - it worked.
Funnily enough I had put my own date of birth in the US format - as instructed - but the website automatically changed it around.
Just caused us a half an hour of frustration trying to work round it - so advice is - if you have trouble ring the help desk!!