@Federico Coppola Thanks for posting in our Q&A.
For this scenario that give the iPhone to a new user, the official method is the Wipe action.
https://learn.microsoft.com/en-us/mem/intune/remote-actions/devices-wipe#wipe
However, it is needed to re-enroll the device after the wipe action.
Currently, all the remove actions will remove the device from intune management. There is no method to keep the device managed by intune after these remove actions.
Thanks for your understanding.
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