You can delete it directly and the device remains in the inventory, requiring you to manually add it to a new network.
Deleting a Network
Networks can be deleted when they are no longer needed. The devices from the network will remain in the organization's inventory and can later be added to new networks. Follow the steps below to delete a network.
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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