I would like to book a separate award ticket for my son who is only 10-year-old and needs the UM service, can I book online first and then call delta to set up the documents? Just tried.. it seems the delta online is asking for birthday and disallow if younger than 15-year-old. Does it mean I have to call? I should not use a wrong a birthday, should I?

BTW, am I right in saying no fee for direct ticketing over the phone except for European countries?