Advanced Steam session - Session found but can't join

Nobodoy has an idea how to solve this problem ?

To be clearer, I want to create a sort of client-server multiplayer on different PC on the same wifi post.
I’m pretty sure that the problem is coming from a firewall issue and maybe a setting inside Unreal, but I have no clue what it is.

Does anybody tried to do the same thing than me ?

Thanks for your help :smiley: