"there was an error communicating with the server" - Forza Horizon 5

For the past 10 months, I've been unable to play fh5 multiplayer (auction house works though but not horizon life or eliminator). I believe that it is because of my Teredo state which I cannot fix in normal windows settings since the Xbox networking, or whatever it is called, option disappeared like a year ago.

Currently, my Teredo is like this:
Type : enterpriseclient

Server Name : teredo.trex.fi

Client Refresh Interval : 20 seconds

Client Port : 3544

State : dormant
-

But I managed to get it once like this (it didn't last too long):
Type : enterpriseclient

Server Name : teredo.iks-jena.de

Client Refresh Interval : 20 seconds

Client Port : 3544

State : qualified

Client Type : teredo host-specific relay

Network : managed

NAT : restricted (port)

NAT Special Behaviour : UPNP: Yes, PortPreserving: No
-
It didn't work though.

Nothing I've tried already has never worked (in case you wish to know all the things I tried: reinstalling fh5, logging out and into microsoft store, restarting my pc, reinstalling network adapters via settings, messing with teredo in command prompt and powershell, port forwarding and enabling UPnP in my router settings, creating firewall exceptions for my port, enabling ipv6 in ethernet status properties, trying to update all network adapters in device manager)

Last two things that I can try are putting my router into dmz (demilitarized zone) which is very risky so I'm not doing that and doing a factory reset to my pc in hopes of resetting teredo back to it's original state as it was. But I've read somewhere that someone has tried factory reset and it didn't fix their similar problem with teredo.

I'm really desperate at this point, I hope someone will help.

:)