It's a crazy itinerary, I'm about to fly BA to AUH, then EY on to JFK, then AA to SFO. All in F, via an AA mileage award redemption.

While I'll shortly board my BA flight, I can't check in for my EY flight (using my EY record locator, on the EY site) online. I just get sent through a seat selection loop (seat already selected and confirmed some time ago), without getting to any check-in confirmation or ability to print the boarding pass.

Is this because a flight to the USA can't do an online check-in? Or because I can''t check in via the EY site for the AA JFK-SFO f;oghjt, so the system prevents any check-in? Or some glitch perhaps unique to my reservation? Or something else?

I assume I can simply go to the transfer desk at AUH to get my boarding pass, especially since I have a 7+ hour connection. Still, I'd welcome any advice on what's going on and on what to do upon arrival in AUH if it's a more serious problem than I'm imagining.

Thanks for any help!