Registering devices with Intune for management and policy enforcement
@mark lefler, Thanks for posting in Q&A. To enroll existing Azure AD joined device into Intune, you can try the method in the following link:
https://call4cloud.nl/2020/05/intune-auto-mdm-enrollment-for-devices-already-azure-ad-joined/
Note: Non-Microsoft link, just for the reference.
Hope the above information can help.
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