Can't add device on border router ZB-T2

Laguna85 · December 23, 2025, 1:54pm

Ehi,

i just bought a ZB-T2 and add it on HA as Thread Board Router.

HA is in the same VLAN of my IOT stuff and i’m using the mobile app on a smartphone in the same VLAN. Ipv6 is enable and also nat64.

What’s wrong? The devices were never used in other matter network and my phone it’s synced with the android credential.
I can’t find any device, zero.

I followed this video and all seems working. Both nuki lock go and goove stuff cant’ be reached.

Restart over and over and waited more then 10min.

I already tried to wipe cache in play services. Wipe cache and data in home assistant and on my phone, in Google > Settings > Services & Device > Thread. I can’t find any network.

Thanks for the help

wmaker · December 23, 2025, 7:16pm

If you don’t see any network, then is is probably because your HA OTBR AddOn isn’t running. Check the logs for the OTBR AddOn and see if it is indeed running or not.

Laguna85 · December 23, 2025, 7:54pm

Ehi,

OTBR is up and running. I can’t post screenshot, so here’s the tail of log.

[20:47:28] INFO: Starting otbr-agent…

[NOTE]-AGENT—: Running 0.3.0-b067e5ac-dirty

[NOTE]-AGENT—: Thread version: 1.3.0

[NOTE]-AGENT—: Thread interface: wpan0

[NOTE]-AGENT—: Radio URL: spinel+hdlc+uart:///dev/serial/by-id/usb-Nabu_Casa_ZBT-2_9C139EAC6360-if00?uart-baudrate=460800&uart-flow-control

[NOTE]-AGENT—: Radio URL: trel://end0

[NOTE]-ILS-----: Infra link selected: end0

59d.00:25:31.585 [C] P-SpinelDrive-: Software reset co-processor successfully

00:00:00.029 [N] RoutingManager: No valid /48 BR ULA prefix found in settings, generating new one

00:00:00.037 [N] RoutingManager: BR ULA prefix: fde2:cde5:9570::/48 (generated)

00:00:00.038 [N] RoutingManager: Local on-link prefix: fdde:ad00:beef:cafe::/64

00:00:00.211 [W] P-Netif-------: Failed to process request#2: No such process

s6-rc: info: service otbr-agent successfully started

s6-rc: info: service otbr-agent-configure: starting

Done

s6-rc: info: service otbr-agent-configure successfully started

s6-rc: info: service otbr-agent-rest-discovery: starting

00:00:05.155 [N] RoutingManager: Local on-link prefix: fdbe:4b0d:b699:cc5f::/64

00:00:05.191 [N] Mle-----------: Role disabled → detached

00:00:05.236 [N] P-Netif-------: Changing interface state to up.

00:00:05.282 [W] P-Netif-------: Failed to process request#5: No such process

00:00:05.675 [N] Mle-----------: Attach attempt 1, AnyPartition reattaching with Active Dataset

[20:47:35] INFO: Successfully sent discovery information to Home Assistant.

s6-rc: info: service otbr-agent-rest-discovery successfully started

s6-rc: info: service legacy-services: starting

s6-rc: info: service legacy-services successfully started

00:00:12.175 [N] RouterTable—: Allocate router id 3

00:00:12.175 [N] Mle-----------: RLOC16 fffe → 0c00

00:00:12.177 [N] Mle-----------: Role detached → leader

00:00:12.178 [N] Mle-----------: Partition ID 0x587a198e

[NOTE]-BBA-----: BackboneAgent: Backbone Router becomes Primary!

00:00:17.113 [W] DuaManager----: Failed to perform next registration: NotFound

Maybe more intresting is the matter log.

wmaker · December 23, 2025, 8:04pm

OK, so now you’re seeing a Thread network. That’s good!

wmaker · December 23, 2025, 8:06pm

What mobile device are you using iOS or Android?

Laguna85 · December 23, 2025, 8:17pm

Android, as i said, i already clean the cache over play services and sync the credential.

wmaker · December 23, 2025, 8:24pm

Ok so you use the HA Companion App (Android) for commissioning a device. What happens … What does the App say, what do the Matter Server AddOn Logs say?

BTW, there is a bit of a bug in the Android framework. You have to do a sync a couple of times to get an actual confirmation (the first time the sync’s confirmation may not actually be correct)

Laguna85 · December 23, 2025, 8:33pm

This is the tail of the Matter Server log.

I already tried few times to change the thread network with a new one, and repeat the operation. But, as i said, a matter over wifi plug device was already discovered, so mdns ipv6 and stuff should works. At this point the culprit seems something broken on my phone.

wmaker · December 23, 2025, 8:43pm

Thread networking is a much more difficult technology, so …

The general problem with Matter over Thread is the credentials in the mobile device are incorrect. Android has the problem with only using the first credentials it finds, and if you tell Android to change, it really doesn’t work, you have to remove not only the cache, but also the storage in Google Play services to remove any Thread credentials. Also be aware that anytime you change Thread networks/reset the Thread network in HA, then new Thread credentials are generated in HA and this has to be sync’d to the Android mobile device that has already had its thread credentials cleared out.

BTW, the log is show subscription failures which usually only happens to devices that were actually commissioned. What you should see when doing a new device commissioning is the logs showing that Matter is going into commissioning mode

Laguna85 · December 23, 2025, 8:55pm

Fully reset play services it’s a nuclear bomb option. If i use another android and creating a new thread network it should be clean enough?
Btw, thanks a lot for your help!

wmaker · December 23, 2025, 8:59pm

It should yes.

Laguna85 · December 24, 2025, 12:18pm

This is beyond a parody.
I nuke everything. Tried on another smartphone and nothing.
Tried to delete all data in play services and nuke all and now guess what?
If i try to add a matter device on mobile now i got an error.

“matter is now not available”

and keep loading and loading and loading.

But here’s the log of matter!
2025-12-24 09:44:54.350 (MainThread) INFO [matter_server.server.server] Matter Server successfully initialized.
OBTR is up, everything is running.

What a f*cking nonsense. I bought HA green and this ZB-T2 to avoid crappy headache like this. I’m techy enough to waste lot of time to fix network trouble but i have servers and lot of docker to play with. I did not want to add more complications.
Lot of ppl have trouble with matter/android but i don’t have and want any apple devices lol.
Thanks again mate.

EDIT.
uninstall and install home assistant on the phone fix the matter discovery infinite loading. But still not working to add devices.

Kyrille · December 24, 2025, 5:14pm

I don’t have this zb-2t but I have the same conclusion: pairing is currently a mess. My advice would be to try Google Home app instead of Companion (or in addition to, it’s not clear to me yet). For a lot of users, me included, it allowed inclusion of new matter devices in Home Assistant. But it’s not magical : it worked fine with Myggbett and Timmerflotte but I am still fighting with Myggspray (all brand new Ikea devices).

HACS-bank · December 24, 2025, 6:37pm

If you have trouble using Companion app, suggest you try using a PC / macOS browser session and see if you learn anything.

This is based on a diagnostic technique known as Divide and Conquer: if there is any element in the system which you can swap for another, swap it and see if it changes anything. You don’t need a reason to suspect any particular element, it is more about proving that the issue is not to do with the element you changed.

(Head of University IT Services / CS Major)

enriqg9 · January 10, 2026, 6:27pm

After hours messing with my router settings, proxmox network adapter settings, reconfiguring matter server, Thread Border Router add-on, clearing data & cache of Google Play Services I finally got it going.

The “matter is currently unavailable” error is originated after wiping Google Play Services on the Android device. Looks like an update is also wiped for the Google matter service that the HA companion app uses to scan QR codes & commission devices, which triggers the “matter is currently unavailable” error.

Here’s what worked for me to be able to commission devices via the ZBT-2.

Configure the ZBT-2 OTBR network and set as the preferred network with credentials
Wipe the Google Play Services storage & cache to clear old credentials of the border router network stored on the Android device
HA Companion App Settings → Troubleshooting → Sync Thread Credentials
Scan any matter QR code with the Camera app and tap the QR code action to trigger Google Play Services to update the matter commissioning service
Go back to the HA companion app & commission matter devices via the ZBT-2 network