I did an integration between slack and azure to enable my users to connect to my slack workspace through azure AD using SAML sso sign in.
The problem is once I have signed in using any browser, when I sign out and try to sign in again I get automatically signed in without even asking for at least a username. So if I want to sign in using another account is not possible.
How can fix this?
This is expected behavior for SSO and you would need to disable SSO if you don't want users to be automatically signed in. The Primary Refresh Token is used to provide a seamless single sign-on experience so that customers are automatically signed in with the account used to log in.
If you were building a custom app and wanted your users to be prompted to give credentials without without disabling KMSI or un-registering/disjoining Azure AD, you would need to update your application code to include either the prompt=select_account or prompt=login parameter in the authentication request. These options are both documented here.