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This is expected if you do not have auto-enrollment enabled. Below official documentation covers this issue and the resolution:
Set up enrollment for Windows devices
"If you do not have Auto-MDM enrollment enabled, but you have Windows 10/11 devices that have been joined to Azure AD, two records will be visible in the Intune console after enrollment. You can stop this by making sure that users with Azure AD joined devices go to Accounts > Access work or school and Connect using the same account."
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