A Microsoft admin from your organization, typically from IT, can follow these to enable Circleback for the organization:
Log in to Circleback at app.circleback.ai.
Once they've created an account, select Connect next to Microsoft Outlook Calendar.
Tick the Consent on behalf of your organization box when connecting the Microsoft account.
Select Accept.
Alternatively, the admin can switch the user consent settings to Allow user consent for apps by following these instructions. Please keep in mind that with this approach, each user consent will need to be approved by the admin.