After creating a new tenant, any immediate attempts to use the rest UI as the newly created admin user return a 403 error.
When attempting to log in as the user, it is noted that the password is expired and must be reset.
Release : 20.2, 21.2
Component : CA Performance Center
This behavior is intentional.
The default admin and user accounts created upon initial product install or when creating a new tenant are created with an expired password.
The password needs to be updated upon the first login for these accounts.