SAML authentication gives unauthorized error after upgrading from 7.9.5 to 8.9

Hello,

We just upgraded from 7.9.5 to 8.9 and all users get the following error. I just checked groups and users and all of them are still available and permissions are correct. I tried to add openid connect and gitlab connect but still getting the same error. New users trying to login are not shown in the users section. Any ideas?
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Hi @uriand ,

As per the LTS upgrade notes:

Additional SAML checks (8.4)
SAML authentication adds additional checks for validating SAML responses from the identity provider. This could reveal a non-standard configuration that needs to be updated. Information will appear in the logs upon a failed login attempt in the event that the configuration needs to be tweaked.

I would advice you to check the server side logs (particularly web.log and access.log) for any error message and share it here.