Twitter Warning: Don’t change username, e-mail or password until further notice
Twitter has posted a notice advising users not to change their log-in details for now, while it looks into a bug.
“We’re currently researching reports from users who are locked out after trying to reset their passwords or change their email address or user names. This seems to affect new users as well as long term users; we do not advise changing your user name, email address, or password at this time. We will update Status with more news as it becomes available.”