Teredo is unable to qualify

As I mentioned in the title I got the Teredo issue that's basically saying it's unable to qualify.

For me it's really important, that I can connect to the xbox live services on Windows 10, because I wanna use the xbox party chat and play with a friend who has an xbox series s.

Until now, I wasn't able to fix this problems. I did have problems with Teredo in the past several time, but I could solve 'em. But now, none of all fixes I could look up on the internet, and yes firstly I also went through the steps which Microsoft hast provided on a support page according to this problem, couldn't fix my issues I have again with teredo. I also tried to solve this, via port forwardings.

So the main problem is not that I can't play online like Forza Horizon or Call of Duty, no I just wanna use the xbox party chat which I can't because teredo is in the way and not lettin' me accesing those services.

Now I'm writing this after I did a entire reset of my mashine and I still get this error message in the settings app under gaming and xbox network.

Now I come up to the point where I dunno else what I should do? I assume that's a problem according to the LAN Controller on my Motherboard which is an Intel I225-V Ethernet controller, or it's something within the windows firewall, which I can't tell for sure!

I hope I'd get some advices and help on this, may someone had this scenario too and could help me solve this problem. It's really annoying, so I'm gonna say it again, it's not my first time that I'm dealing with a teredo issue

:)