Cannot see/ search/ direct connect/ join on my private servers!

Game mode: Online private
Type of issue: Cannot see nor connect to privates servers of my choice
Server type: PvP
Region: EU, France

3 days ago, I was playing with friends on a private server called Canard Exiles, that was in my favorite list of servers. I had another favorite server too.
2 days ago, the “Canard Exiles” server disappeared from my fav list, I was unable to search for it (no result), a Direct Connect will give me a time out answer, if I try to join a friend that is already in the active and working server, Steam says that the server is nowhere to find.
I tested and diagnosed my connection and it is great (fiber, no lag, good pings on a normal adress, clean hosts file, clean DNS cache w<ith tries on different DNS etc), and outside this very Conan Exiles private server problem, everything is fine !
I tried a Traceroute on different servers, and the tracing stops before the servers themselves, for the one I tested (It work on a random official one).

Yesterday I did try the other favorite in my list that was still displaying, and I could connect.
BUT THIS MORNING NO MORE FAVORITE !!! What is removing my favorite servers from my list, and why are they just unable to even ping when I KNOW THEY ARE UP ??

1/ go to the online list of servers, and search “Canard Exiles”, or try a direct connect on, or even try to join a friend that is IN THE SERVER already (from the steam app)
2/ get a “no server found”, or a time out, ot a “server not existing” from Steam…
3/ favorites are removed from the server list as they do not appear anymore.
4/ ping/ traceroute the address “” from my PC : no success.

All of the above with testing from admins from the server, and server is active and working.