Entra ID SSO with ServiceNow Integration issue

[HP8]

I've enabled the Multi-SSO plugin and have everything set up between Entra ID and ServiceNow for SSO. Everything works fine for a standard ITIL user on the sys_user table. We have portal-only users on the customer_contact table which are viewable on the sys_user table, so I've tested a user created on this table, made sure the user entries are on both the Entra ID (guest user) and ServiceNow. I know that Entra ID has synced this test user to ServiceNow because it has updated the user record with some groups.

The issue I am facing is that after logging in through IDP, the test user is immediately taken to the Logout Successful screen e.g. /external_logout_complete.do

What am I doing wrong here?

[Old Jonesy · Accepted solution]

I'm certain you've figured it out by now, but what I've found is if this is the first time that account is logging into the instance have them try accessing via [instance name].service-now/login.do

This gives the account a chance to authenticate and select the SSO login option.