Booked a flight via a TA, as an AY Codeshare (I try to avoid these types of messes for this reason but the savings was substantial) Tried both the TA less then 24 hours and standard BA details page. It's refusing to hold my API Data and my AA Number. :/ and when trying to purchase a seat, it takes me in an infinite loop through Finnair's Website back to BA. Will give it a few days before giving them a call.