Originally Posted by jsloan

Normally this gets picked up during the check-in process, which should have noted that there was no ticket attached to the reservation and flagged it for airport processing. The only unusual part is that they didn't catch it until the gate. I've only had that happen before when my ticket got messed up during a VDB attempt.

Did you attempt to upgrade with an instrument? That can lead to the reservation getting out of sync after a schedule change, although, again, it should have been noted during check-in.