In order to create an App Registration in Azure to allow Oauth methods when contacting the Office 365 Service Communications API follow these steps if using delegated permissions.
NB: Grant any permission your current task requires.
- Open portal.azure.com and go to App Registrations.
- Choose + New registration
- In the Register an application form provide a name (O365ServiceApi)
- Select Accounts in this organizational directory only
- Choose Register
Here is a visual representation of those steps:

Now let's give the app some permissions.
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