The default way to log in to your Blogin account is by typing your username or email and a password on the login screen.
However, there are several alternative ways to log in, that may work in your situation.
1) Sign in with Google
If your organization is using Google (G Suite) as the company email provider then you can allow people from your organization to log in to BlogIn by enabling the 'Sign in with Google' option on the User Authentication tab on the Settings page.
2) Sign in with Slack
If your company is using Slack you can allow users to log in by enabling the 'Sign in with Slack' option on the User Authentication tab on the Settings page.
3) Sign in with SSO
If your company is using a Single Sign-On (SSO) provider, you can allow users to log in via SSO by setting up the SSO connection on the User Authentication tab on the Settings page.