He needs to ask to who sold it to unclain from the existing organization. An advice, Meraki support is not authorized to unclain it for you, so don't ask for Meraki support.
Unclaiming Devices
- Navigate to the Organization > Inventory page.
- Check the box for the device(s) to unclaim.
- Click Unclaim.
- The device(s) will disappear from the list.
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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