Gents,
About a month ago, AMA started rebuilding their site. I had a bit of trouble getting back in, and the welcome page looked a lot different.
What worked was using a variant of my username and requesting a new password. In effect, I guess, that overrode the old account info tied to my AMA #. Still have to log in with the variant of username, and new password.
It is worth a bit of frustration to get through the gate- the internal navigation seems better than the old site.