Remember that in NAT mode, the Access Point's IP is used for communication, and if you need to access an internal resource, NAT mode is not recommended.
Also remember that Meraki MV cameras are designed to work best in Bridge mode.
For cameras that went offline, you’ll likely need to reset them, or you can try reboot them.
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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