Login travis-ci.org failed

When I try to login with the command:

travis login --github-token my-token
xxxxxxx has not granted Travis CI the required permissions. Please try re-syncing your user data at Travis CI - Test and Deploy Your Code with Confidence and try logging in via travis-ci.org

I am trying to generate token for an open-source project on travis-ci.org according to API Developer Documentation - Travis CI.
However, I cannot login to the site travis-ci.org.
Is this site still available?
How can I generate token for open-source projects on the travis-ci.org (the ceased site)?
I can generate token successfully with the command travis login --pro --github-token my-github-token.