@Medea, Thanks for posting in Q&A.
From your description, I know you got some error while do Autopilot enrollment.
Based on my research, when we do Autopilot enrollment, the device will be identified as Corporate with or without corporate identifiers, therefore, blocking personally enrollment will not block Autopilot enrollment.
For the error message, please check if MDM is blocked in Device Restrictions on the Intune platform, and if so, allow it, which may also be the cause of the error.
Or you can check if you can successfully enroll Intune by excluding the user you want to test from the restriction.
As for corporate identifier show Not contacted, please check whether you enter the correct manufacturer, model, and serial number.
Please check above information, if there is any update, feel free to let me know.
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