Registered commenters can log into their account several different ways using a register username or email address and password.
Using the Disqus: Login page
Through the embed:
Using a social login
Disqus offers several social login options (Google, Twitter, and Facebook), which allow users to authenticate and comment. While logging in with a social account allows users to edit their previous comments, they are not the same as registered accounts.
If you'd like to use a social account to log into your registered Disqus account, it will first need to be linked to your Disqus account.
Some sites may use what is called Single Sign-On (SSO) which allows you to comment on Disqus through their own account system.
Sites using SSO can often be identified by the SSO login button found on the embed.
If you're having trouble logging in, we'd recommend contacting the moderator of the site in question. Since this is a completely different account system from Disqus, they will be able to better assist you since they have access to the user database for which you're trying to sign-in.
If you're having trouble logging in as outlined above, kindly see our Login Help documentation for troubleshooting steps.