Looker SSO using Okta identity provider is throwing error 403

This errors 403 & 404 are getting from LOOKER after clicking the Authenticating button & as well from ‘Test SAML Authentication’ button after entering the login credentials.

The credentials were tried using the email address/oktaid, both didn’t work as expected.

Can you please provide the steps how we can figure out root cause of the issue ? Attaching the looker log file where we couldn’t find any issue,

“Could you please let us know what attributes core product expects to be present? We currently only have access_user_id. Is there a need for any additional attributes ?”

Can anyone please suggest how we can find the root cause of the issue

Thanks,
Satish