Hi @Tanner · Thank you for reaching out.
The callback url is also known as Reply URL or Redirect URI. To update the callback URL, you need to update the Redirect URI registered in the application.
For this purpose, you need to perform below steps:
Azure Portal > Azure Active Directory > App Registrations > Search the application by using App ID or Name > open the app and click on authentication blade > update the Redirect URI.
Note: To perform above action, you need to have application administrator or cloud application administrator or global administrator role assigned to your user account.
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