Follow these steps to connect Sharepoint via the StackOne Hub successfully.
Log in to Microsoft Azure
Navigate to App Registrations
Register a New Application
Configure Application Details
https://api.stackone.com/connect/oauth2/sharepoint/callback
Obtain the App Client ID and Tenant ID
Obtain the Application Client Secret
Set the Application API Permissions
Grant Admin Consent for Application Permissions
Add Single-Page Application Redirect URI
https://app.stackone.com