Problem

A Mac keeps showing up as company owned when erased or setup, even though it was released from ABM, removed from Jamf and their operation system wiped.

Possible Issue

The order of operations was wrong, the computer was wiped before it was removed, or some other reason kept it from being registered for removal.

Solution

It all starts with how you removed them from Jamf and how\if you released them from ABM (either through Jamf or directly in ABM).
Remove a mac from Jamf:
https://docs.jamf.com/best-practice-workflows/jamf-pro/unmanaging-mobile-devices-computers/Unmanaging_Computers_from_Jamf_Pro.html
Release a device in ABM:
https://support.apple.com/en-il/guide/apple-business-manager/axmec4d28461/1/web/1
if you did release them and they show up as "removed" in ABM, and it still tries to enroll after re-install, then you should try erasing the mac again (from recovery or external OS) before re-installing, but in the following manner: