I've had errors like this multiple times when trying to log in, in incognito/private mode. Another "error" when private mode was toggled was that calendars with fares for different days/destinations has not been showing at all (even if you'd pick specific dates). The pages just keeps loading forever and never shows you any prices...

Seems that KL/AF/Flying Blue really wants to track and save the history of our searches, so that they can jack the prices up even more....