If the SAML authentication has been activated in your instance and the session gets destroyed when clicking on "User and permissions" or "User Profile" it's possible this is due to a user password which expired before the activation, a typical use case for this would be an account that was invited to the system while local based authentication was enabled which had the password set to expired.
To solve it you can run the following query, replacing <user_name> for the affected username :
update users set password_expired ='f' where username='<user_name>';
This query can also be run, to update the value for all the users:
update users set password_expired ='f' where password_expired = 't' ;
If you are facing this issue on a SAAS instance please open a support case.