I booked a trip on the aa.com website flying MAA - HKG - LAX - PHL in the month of September. The flights from MAA-HKG and HKG-LAX are operated on Cathay metal. This was a very good fare at $648 for Economy!

However, I am unable to make seat assignments on the Cathay flights when I enter the Cathay PNR number. They point me to American as they issued the ticket. My Aadvantage number is listed on the reservation.

American says they have no insight into Cathay's seat assignment and ask me to talk to them. So in the end, both airlines point to each other! See screenshots.

I have status (One World Sapphire) which does give me access to pick exit row seats for free, but it doesn't help if both carriers point fingers at each other.

Strangely enough, I am able to make a meal reservation on the Cathay flights. The seat assignment is the problem.

Do you know how I can get this sorted out? I do not want to show up at the airport and get the dreaded middle row seat next to the toilet for the 13 hour trip to LAX...