This happen both Original ZH and other mod like shockwave. Not matter whatever SWR.net is on or off, always happen, and my internet still working correctly.
I have no idea how to fix it, I using Origin Ultimate Edition.
I have played ZH for many years, this problem I haven't seen before

yeah i get this a lot as well, just go back into the lobby it should all still be working fine.
if it isnt just restart the game.

No, it still happening, this bother me since a few days ago, I tested for many days, everyday, and even restart my computer for many times, unlucky, it isn't one is worling.

in that case reinstall swr net itself.

the installer and uninstallers are both in your zero hour folder.

SWR.net_Unistaller.exe
and
SWR.net_Installer.exe

and make sure you run both as admin
see if that fixs your problem.