Hello @ByronNectar
Not sure if I can be of any help to you.
When you say it stopped working suddenly, when did that exactly happen? 5 or 6 weeks ago? If so it might be a bug in the Firmware of the GX20.
There went something terribly wrong with the latest firmware-upgrade, mostly for PoE devices. After firmwareupgrade my GX20 shows a device connected on Port 6 on the GX20. Keep in mind the GX20 has only 5 physical Ports. I am still waiting for a fix on the firmware.
If it stopped working 5 or 6 weeks ago, file a support ticket with Meraki and ask them to reset the firmware to the older version on your GX20.
You might also want to have a look at Meraki Go - Wired Networks (VLAN) - Cisco Meraki
Cheers