Same here for a flight, but I wanted to be sure I kept the P fare I booked (or was trying to book) so I tried farelock for the heck of it and for some reason, the card went through for that. The on hold flight shows up in My Trips but when I try to purchase it, no go. I couldn't get through to UA so I called Chase. They said they were getting inundated with calls about this and have alerted UA - for what it's worth.