Yeah, that's a classic Windows licensing quirk - even when you install from VL media, Windows 10 will often auto-detect and inject the OEM key stored in the BIOS. That's why your image keeps reverting to the OEM key instead of staying on your MAK.
The best practice here is to:
Run sysprep /generalize before capturing your image to strip any activation info.
After deployment, use slmgr /ipk <your MAK key>, then slmgr /ato to activate.
You can also disable automatic key retrieval from BIOS by adding a generic VL key temporarily during setup.
If you ever get tired of juggling MAK vs OEM licensing and just need independent retail keys (especially for standalone machines), Digitlogs.com has legit retail Windows 10/11 Pro keys that activate cleanly without BIOS conflicts I've used them a few times for smaller deployments, no issues at all.
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