1. Network Traffic or Interference
Symptoms
OTA fails to start
OTA stalls partway through
OTA appears to complete, but may not
Cause
Zigbee OTA updates are sensitive to network congestion. Heavy Zigbee traffic or attempting to update multiple devices at once can cause the update to fail or behave unpredictably.
Resolution
Update one switch at a time
Ensure minimal Zigbee network activity during the update:
Avoid pairing devices
Avoid running automations that heavily use Zigbee
If possible, perform updates during low-usage periods
2. Switch Is in a Bad Running State (Requires Air-Gap Reboot)
Symptoms
OTA will not start
OTA fails immediately
Switch behaves oddly or is unresponsive
Cause
Occasionally, a switch can enter an unexpected internal state that prevents OTA from functioning correctly.
Resolution
Pull the air-gap tab on the switch (this fully cuts power)
Wait 2-5 seconds
Push the air-gap tab back in to restore power
Retry the OTA update
3. OTA Is Running but the UI Does Not Show Progress
Symptoms
OTA appears stuck at 0%
No progress indicator in the hub UI
Update seems idle, but the switch is actually updating (LED flashing green)
Cause
Some hubs do not properly reflect OTA progress, even though the update is actively occurring in the background.
Resolution
Wait for the LED bar to reach 100% and for the switch to reboot
Manually query the
swBuildIdfrom thegenBasic(Basic) clusterIf the
swBuildIdchanges to the new firmware version, the OTA completed successfully, even if the UI never showed progress
4. Rare Issue With Early VZM31-SN Production Batches
Symptoms
OTA reaches 100%
Switch reboots
OTA can be applied again after this process
The update completes repeatedly in a loop
Cause
A small number of early production Blue Series (VZM31-SN) switches may not properly finalize the firmware after a successful OTA.
How to Confirm
Please verify all of the following:
The OTA process reached 100%
The switch rebooted afterward
The switch allows the same firmware file to be applied again and repeats the process
Resolution
Contact Inovelli Support
Provide either:
Your order information, or
The date code from the sticker located under the wallplate
Support will guide you on next steps once this information is reviewed.
Still Having Issues?
If none of the steps above resolve the problem, please reach out to Inovelli Support with:
Your hub model
Firmware version being applied
Approximate failure point (if any)
Any error messages shown by your hub
We’re happy to help get things updated smoothly.