SOS - Please, need urgent help after update for Mac OS Big Sur


I’m writing in place of a friend’s son with Asperger Syndrome who is in need of urgent help, as he has a deadline to submit a project.
He made his project on a Mac, I believe with Python 3.8 and Home Assistant, and made an update from Catalina to Big Sur 11.1. He had everythink working, a project to remotely assist help elder people taking their medication using a lights and buttons system.

Now, for every script he tries - like light.turn_on on this example - he gets this:

`2020-12-31 19:08:20 ERROR (MainThread) [homeassistant.components.automation.nova_automacao] Acender Lampada: Error executing script. Service not found for device at pos 1: Unable to find service light.turn_on

'2020-12-31 19:08:20 ERROR (MainThread) [homeassistant.components.automation.nova_automacao] While executing automation automation.nova_automacao**

'Traceback (most recent call last):

File “/Users/luis.moreira/homeassistant/lib/python3.8/site-packages/homeassistant/components/automation/”, line 404, in async_trigger

await self.action_script.async_run(

File “/Users/luis.moreira/homeassistant/lib/python3.8/site-packages/homeassistant/helpers/”, line 1026, in async_run

await asyncio.shield(run.async_run())**

File “/Users/luis.moreira/homeassistant/lib/python3.8/site-packages/homeassistant/helpers/”, line 242, in async_run**

await self._async_step(log_exceptions=False)**

File “/Users/luis.moreira/homeassistant/lib/python3.8/site-packages/homeassistant/helpers/”, line 250, in _async_step

await getattr(

File “/Users/luis.moreira/homeassistant/lib/python3.8/site-packages/homeassistant/helpers/”, line 469, in _async_device_step**

await platform.async_call_action_from_config(**

File “/Users/luis.moreira/homeassistant/lib/python3.8/site-packages/homeassistant/components/light/”, line 76, in async_call_action_from_config


File “/Users/luis.moreira/homeassistant/lib/python3.8/site-packages/homeassistant/”, line 1395, in async_call**

raise ServiceNotFound(domain, service) from None

homeassistant.exceptions.ServiceNotFound: Unable to find service light.turn_on`

Any help would be truly welcome.


Looks like the lights got lost in the update. The error is complaining that the light.turn_on service couldn’t be found, this is the case when no lights are available in the system.
Tell your friend to check the config of the lights and set them up again if they are missing.

Thanks, I’ll tell him.


Are those Philips Hue lights? I had the same error even though the lights were still showing in HA and had to remove and re-add the Hue integration.

No, but it seems that he managed to solve his problem. Thanks.

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