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1,Are MDM and MAM user scope both enabled for all users (or the same groups of users)? If yes, for Windows BYOD devices, the MAM user scope takes precedence, so the device will not be MDM enrolled and not be visible in Intune.
2,We can try to turn off MAM user scope, delete the device from Azure AD, disconnect the account on the device, then connect it again, and join to Azure AD and enroll to Intune.
For more information, please refer to:
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