Have you use workspace user to log in? If it is a new workspace, it will be an administrative username you created during workspace creation. If you don't remember, you can try to reset its password from the logon screen.
Or you can reset the password, by logging on to INTERNAL workspace where you can manage all workspaces there.
If you don't remember "admin" username to logon to INTERNAL workspace, you can reset it using the apxchpwd.sql script.
Thanks for the reply. I finally figured out what to do, but I am not sure I truly understand why. In any case, I am now able to login & use the workspaces I created.
Glad to hear that.