Hello,
Best wishes to all for the new year 2022.
So, I just bought a Zigbee 3.0 USB key from Domadoo to replace my old key, which works quite well except that the range is limited. That’s why I saw that the key sold by Domadoo is equipped with an antenna, that’s the reason for my replacement.
So I simply removed the old one and reconnected the new one, and there it is impossible to configure the new key, no green check on the Gladys/Mqtt/Zigbee2 links.
So I put back my old key and it is immediately recognized and validates my config.
To summarize, it works with the old key, but not with the new one.
I have an old raspberry loaded with Gladys V5 but not configured, and there my new key was recognized and validated my zigbee2 config.
I think you need to remove the old key before connecting the new one, but I don’t know how to do it, can you tell me how to do it? or another solution. THANK YOU!!!
Is the USB port path defined by the OS the same?
It might have changed, and in that case, it needs to be updated in the integration settings 
After that, I’m not sure if Zigbee2mqtt handles a key change « on the fly ». You might need to restart the container (or the Pi, that way you’re safe).
When you talk about the path of the USB port, it’s the USB port where the Zigbee2mqtt dongle is inserted.
If that’s the case, the USB port of the new key is (/dev/ttyUSB0 -iTead-10c4) and the old one is (/dev/ttyACM0-Texas instruments-0451) and I have taken care to modify the correct key in the settings.
When you talk about restart, it’s a reboot of the pi, because I don’t know the command to do it for the container.
Indeed, because I think the container pairs for the first time with the inserted USB key.
Either way, both have the same effect
docker restart CONTAINER_NAME
To restart a container.
In the case of Zigbee2mqtt, the container name is gladys-z2m-zigbee2mqtt, so I think you can restart that one in theory it should connect to the new key on restart:
docker restart gladys-z2m-zigbee2mqtt
After this case hasn’t been much thought out I think, so I can’t guarantee anything, we’re feeling our way!
Hello,
I just did your manipulations! The Zigbee2mqtt container stopped properly after the restart, but the new key could not be validated and the Zigbee2mqtt container did not restart.
As soon as I reinserted the first key installed at the start of Gladys, everything returned to normal (restart of the Zigbee2mqtt container, and the inserted key validated in config).
In conclusion, you should not change the Zigbee key while using Gladys, otherwise you will have to reconfigure Gladys in its entirety.
Have a nice day and thank you for the help!
@jerome You confirm that you had another Zigbee key before that worked and you can’t change the key like @Jac34?
For this, I admit that you should find out more on the side of Zigbee2mqtt which is a project in its own right (their doc: Getting started | Zigbee2MQTT), you should find out what the procedure is to change the key on an existing installation.
If there is nothing in the documentation, they also have a forum: Koenkk/zigbee2mqtt · Discussions · GitHub
Yes indeed I confirm that I had a working key before but it didn’t capture very well hence the change.
I will go and check on the website or the forum to see if there are similar cases.
Ok, keep us posted @jerome! 
There is a point that talks about it in their FAQ:
After that, it’s not very user-friendly 
The solution is to have a fresh configuration on the Zigbee side and re-pair the devices.
You will need to use the command line to fix it.
I will make a post (I went through this a few months ago)