I've had this happen to be many times over the years. In the past, it took a little extra work by just calling AA Web Services. They'd confirm what you're seeing on the AA.com and get someone on the line who could help book the lower price on website.

Nowadays it's much worse, unfortunately. Ever since AA moved their tech support offshore, calls with them have been excruciating and long. (Did I mention excruciating?) It now takes on average over an hour to get them to resolve these types of situations. And be prepared to be transferred multiple times, having to explain the situation to someone new each time. If you keep pushing hard enough and repeatedly asking for a supervisor who can override the price, then you'll likely get somewhere. Have a bottle of wine/liquor nearby though...you're gonna need it.