Thread necromancy but I'm running into this same problem this year. I have a PNR for a lap child and when I call United they can see the reservation as attached to the correct award reservation with 2 adults.

However, I have failed to obtain a receipt, eticket number or anything else from United via email despite 3 separate calls where the agent states he's sent the receipt to my (correct) email address. Any ideas besides calling another dozen times? I really prefer not to have too many people touching the reservation as we all know that the more things get handled, the more likely they are to get messed up.