I've had this problem a number of times. Seems to be when trying to click through on multi-city itineraries. And like a previous post or two, when I remove a certain city the problem goes away. Most recently, I was having a very hard time getting anything in or out of PDX to price as advertised. The deceiving thing in this is that while I understand the price may go up for some crazy reason (inventory sapped up before I click purchase) it should not then go back down when I exit and repeat the exact same search.

AA needs to step up and fix this issue.