Flying tomorrow on a domestic flight and got the can't check in online flag. First time happening for me (on hundreds of AA flights) and it's my first time travelling with my new employer (and they booked it). Called AA just to make sure and the slightly uninterested agent didn't seem to see any problems with the reservation.

I normally travel with just my first and last name but my booking has my two middle names on it. That coupled with my KTN and I wonder if that's throwing things off.

Edit with update: Got to the airport a bit early but didn’t seem to have any real issues. Agent at JFK Flagship checkin tapped away a bit, asked for my KTN as apparently that got scrubbed somehow (despite it being against my company’s profile with Amex and adding it on AA.com after I booked). Took a few minutes, got TSA PreCheck. All good and could access mobile BP on the app at that time too. Let’s see how it works when I fly home on Friday.