As an Admin or Billing Moderator, you can request team members with the same email domain to sign in with their Google emails. Using Google credentials as verification increases the security of your Circle.
1. Go to your Circle's Dashboard
2. Select the Security tab
3. Click the toggle to turn Google sign-in on/off
4. Select enable
When enabled, your team members must use Google sign-in in order to access the Circle.
Note: you can only enable this feature if you have a Main Circle, it is not available for Custom Circles as there is no shared domain.You can learn more about Main and Custom Circles here
Only Admins and Billing Moderators can enable this feature