Chase Ultimate Rewards - Ultimate rewards flight booking down?

I am trying to book a flight with Ultimate Rewards travel to earn the extra point/$. When I click on "Book a Trip", it goes to https://go.reardencommerce.com/sp/ACS.saml2 and just sits there until the browser gives up. If I hit refresh, it spews an error message at me about replay attacks. I've tried multiple browsers including a vanilla Firefox. Anybody else having trouble?

Edit: worked on the 5th try.