Set the default web interface for your company
In order to access the admin interface, your account needs company manager permissions.
Company managers can change the interface their team signs into by default. 

From Classic Webtop:
  1. Sign in  to workplace_.
  1. Select the Administration tab on the homepage. 
  1. Under Company Management, click Company.
  1. At the bottom of the page, click Edit.
  1. Next to 'Use Workplace Online by default' tick the checkmark.
  1. Click Save changes.

Next: