Thank you for posting this in Microsoft Q&A.
I understand you are facing an issue while adding your Microsoft account to the Goodnotes Limited app for backup on your iPad.
Your Goodnotes Limited application requires admin approval. The global administrator is the only one who can give consent to your application.
https://learn.microsoft.com/en-us/entra/identity/enterprise-apps/admin-consent-workflow-overview
If you are a global administrator, you can review admin consent requests
If you are trying this in work on application which is configured in "Microsoft.onmicrosoft.com" tenant, then you will need to submit your request in http://aka.ms/itweb/filloutaform This will be handled by internal Microsoft team (MSIT).
Hope this helps. Do let us know if you any further queries.
Thanks,
Navya.
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