Hello @Scott Pendleton
Welcome Microsoft Q&A forum!
Admin roles are defined at different scope = (Subscription & Directory/Tenant).
Global admin is the supreme role defined at directory level to:
- Manage access to all administrative features in Azure Active Directory, as well as services that federate to Azure Active Directory
- Assign administrator roles to others
- Reset the password for any user and all other administrators
Contributor role is defined at subscription scope to:
- Create and manage all of types of Azure resources
- Create a new tenant in Azure Active Directory
- Cannot grant access to others
Though you have Global admin permissions but that doesn't suffice the requirement. You need contributor permissions too.
To better understand roles, please refer to this link - https://learn.microsoft.com/en-us/azure/role-based-access-control/rbac-and-directory-admin-roles#azure-roles
Just as a reference - Azure Migrate support matrix
Hope this clarifies!
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