Do you have MFA enabled and conditional access policy? Check below points if it helps :
If your organization requires multi-factor authentication (MFA) and you receive an authorization error, your conditional access policy may not be configured correctly.
- One workaround is for the administrator to disable MFA for these users during Mover migrations.
- Otherwise, you'll need to contact "Azure Identity" support for help with configuring conditional access policies.
Hope this helps.
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