I flew an international itinerary leaving last week, returning yesterday. Every time I checked it on-line, united.com said that my Secure Flight data were incomplete. I'd complete it and save it. The check box would go to green. Next time checked the itinerary, the same problem was back. Interestingly, I checked again this morning, even though I've flown all the flights, and it's back to incomplete. I completed it and saved it yet again!
Bruce