Everything was fine in the previous version of the update,
The day before when we updated with a girl minecraft we can't play together.

The case is as follows:

On two clients, mine and my girlfriend, there is a connection to external servers, e.g. hive.
We see each other on xbox companion and xbox in windows 10.
For me the nat connection is average, my girlfriends open.
I have options to add ports in the router, after adding on nat is average.
I reset and reinstalled minecraft on both computers.
Neither of us can connect to the other person's game, me to the girl and the girl to me.
Recreating the ported world didn't change a single thing.
Creating a new world didn't help.
Game reset, computers didn't change anything.
We don't have access to 1.17.2.
Turning off the firewall on both devices did nothing.
I spent two days trying to fix the problem myself, but to no avail.

Edit.

When I went to my girlfiends place and tried to connect us trough same wifi, everything was fine.