@Admin Thanks for posting in our Q&A. From your description, did you mean that you want to remove these devices from the business where you bought them? If there is any misunderstanding, please correct me.
Did you have an Azure AD account of this business? If yes, it is suggested to try to remove devices via company portal app.
https://learn.microsoft.com/en-us/mem/intune/user-help/unenroll-your-device-from-intune-windows#remove-in-company-portal-homepage
If not, please understand that the devices are managed by this business now and we couldn't do any change. Given this situation, it is suggested to contact the IT of this business and ask the IT to wipe the devices.
Hope it will help.
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