I can only guess that you forgot to hit the Save Changes button after you did the editing.
One useful thing I've discovered; Sometimes I'll be editing a profile and get distracted by something else. By the time I get back to the profile and try to save my changes, my login has timed out and the Save Changes button just takes me to the login screen.
When that happens, you can log in, then use the Back button on your browser to get back to the edit screen, save your changes, and nothing is lost.