@Vladut Mihai Poncea, Thanks for posting in Q&A. From your description, it seems when we enroll via sign in company portal. It only creates the record in Intune. It doesn't register into Azure AD. If there's any misunderstanding, feel free to let us know.
Based on my experience, if there's any old device records existing in Azure AD. It will cause the issue as ours. You can delete the device in Intune and delete all the records of the affected devices in Azure AD. Then do the enroll again to see if the issue persists.
However, if the issue persists, please collect the following information to us to clarify:
- How many iPhone devices are affected? Is there any iPhone can enroll successfully?
- which enrollment method we use to enroll the device? BYOD or ADE?
- When Sign in company portal, is any error we getting?
Please try the above action. If there's any update, feel free to let us know.
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