You're looking for an MDM (Mobile Device Management) unlock tool that's free.
Have you successfully removed an MDM lock using a free method? Let us know in the comments below. If you are an IT admin, please do your part and release old device serial numbers from Apple Business Manager before you recycle them!
These tools are widely used in the GSM community for Android and iOS devices:
If you have authorized access to the managing account, removing MDM is always free and permanent.
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