Matter over Thread just wont work

[normal tide]

Hey everyone. I am rather new to HA configuration and am currently trying to setup my Matter Server to have it work with a Thread network. I have a Nabu Casa ZBT-2 which is connected to my pi5 and configured as a Thread Border Router. I have done the simple integration config for this one. I have also checked over console as well as Hardware listing that it is connected properly.
Now, even though my Thread Network should be running smoothly, whenever I try to add it to my Matter Server (which it for some reason doesnt do automatically) it just does not do it. I have even typed my Thread network ID into the Matter addon and the Log shows that Thread credentials are inserted ("true") but whenever I try to add a new Thread device it tells me that I need a Thread Border Router. I just dont know what to do anymore because I have already sunken multiple hours into researching and have set this up at least 30 times by now and every time everything looks fine but nothing actually works...
If anyone has encountered something similar before or has any Idea how to solve it I am open to any suggestions because I am truly losing my mind when I see how easy other people have it with the same setup.

If needed I can also provide Logs and screenshots.
Thanks for everyone trying to help in advance ❤️

[pure sphinx]

Well, that's not a nice start with Home Assistant. We probably need some more information.

Just to be sure: you do have both apps (Open Thread Border Router and Matter Server) and all integrations (Matter, Thread and Open Thread Border Router) running?

How do you try to add a Thread device? Companion App, Web UI of the app, through Home Assistant settings? What device are you trying to add?

[vague yarrow]

Check out this video that explains Matter over Thread.

https://youtu.be/yG-41bbeJAs?si=8gTPa_-aLRBGDfkA

[somber ferry]

We are at a strange place where the 'stable" default Matter server and stable default OTBR software in HA is less stable/capable than the current beta options. HA doubled down with its Thread/Matter devs over the last 3-6 months and very slow going over the last couple years is making significant progress.

The default Matter server (python Matter server) is end of life, and a faster, more capable and stable (especially in regards to thread) Matterjs Server is available as a public Beta. from the Matter Server APP config page.

Not advancing quite as quickly, but a similar for the OTBR. older stable was thread 1.3 spec, newer beta is Thread 1.4 spec and behaves better as a result.

Is HA your only ecosystem? any Apple, Amazon, google, smart things etc ... thread border routers in the home?

What mobile device are you attempting to use to onboard new Matter over thread devices ... iphone, android?

Have you synced your thread credentials to that specific phone in the Mobile app?

[clear sleet]

Syncing thread credentials to my phones home assistant app helped me at least get it to try and add a device

[uncut laurel]

was about to refer to the beta as well haha. Thought I'd share my new wisdom cause it seems many struggle with Matter/thread in HA and yet here you are already :D I messaged a big German HA youtuber to cover the topic as well to maybe reach more people.