Device shows twice in Intune and Entra after upgrade, still not activating Enterprise

Hi everyone — I'm looking for advice on a device we're trying to onboard into Intune with proper licensing and Entra join.

Background:

I have a user whose device was:

• Originally on Windows 11 Home
• Manually upgraded to Pro using a generic key (unactivated)
• Then upgraded to Enterprise using a generic key
• Factory reset in an attempt to trigger proper OOBE and Entra join

Current Problem:

Now, we have two device records for the same machine in both Entra ID and Intune:

• One device is marked Entra registered (personal), showing Windows Pro
• The other is Entra joined (corporate), showing Windows Enterprise but still not activated (0xC004C003)
• The user is correctly signed in with their work account
• Device did not trigger the expected work/school OOBE flow
• Subscription activation is not completing

What I've Tried:

• Factory reset and cleanup using slmgr /upk and systemreset -cleanpc
• E5 license is properly assigned
• Verified login during OOBE is using the correct organizational account
• Device shows as compliant and managed in Intune
• But Windows remains unactivated on Enterprise

What I'm Wondering:

• Could the duplicate records (personal and corporate) be interfering with activation?
• Should I delete both and start fresh?
• Is there a better way to force clean OOBE + Entra join when recovering a Home device?
• Should I stop using generic product keys and let subscription activation take over?

Any insight would be hugely appreciated — I'm in the middle of deploying Intune across 75 devices by the end of August.

Thanks in advance!