Why can't I access the platform?

Only users with the Super Administrator platform role have access to platform administration through the gears icon.

If you don't see these gears above the Help Center, it means you lack the authorization for platform administration:

Authorization is granted through the platform role "Super Administrator." Contact your administrator if you believe you should have this role. You can find your contacts through the Help Center.

As a user with the platform role "User Administrator", you do not have access to the entire platform administration and therefore do not have the gears icon in the menu. Instead, you access user platform administration through the user administration in the database and the "Edit account information" link: 

You can read more about platform roles here.