Hello @James Weatherhead
Thank you for reaching out. Reading through the explanation you shared I assume you have same email registered as Personal as well as Work School account you would not be able to invite Account B to directory in which Account A resides. For more details about this overlap you can refer: Cleaning up the #AzureAD and Microsoft account overlap
To share a clear explanation let us take below example.
- Sub A is under Work School Account A (firstname.lastname@example.org) within directory A.
- Sub B is under your Personal Account B (email@example.com) within directory B.
If you do not want to move the billing from Account B to Account A, you can follow this approach:
- Since inviting Account B to directory A, is not possible you can try to perform following workaround.
- Create a new user Account C in Directory B.
- Add this user Account C as Owner on the Subscription and Global Admin on the directory B.
- Invite this Account C to Directory A.
- Later follow the steps mentioned on following article to change directory of the subscription: How to Change your Azure Directory Tenant.
If you would like to move the billing of the subscription from Account B to Account A, you can follow this approach:
- You can perform billing ownership transfer of your Azure subscription from Account B to Account A.
- This would make your Account A as the Account Admin as well as Service Admin/Owner on the subscription and also change the directory of the subscription to Directory A.
- You follow the steps as listed on following document to know more about billing ownership transfer: Transfer billing ownership of an MOSP Azure subscription to another account.
- If you face issues performing this you can create a Azure Support Request with Azure Subscription Management Support to help you with completing the transfer.
I hope this answer helps to resolve your issue.
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