Dying Light 2 Stay Human Network Disconnected error code, explained

gamepur.com:

While Dying Light 2 Stay Human is available to play, some players are running into issues with the “Network Disconnected” error code while trying to play coop. It takes a couple of hours of gameplay to unlock coop in the game, and after that, you would hope it would all be smooth sailing.

Unfortunately, lots of players are getting hit with the Network Disconnected error. If you are worried that something is wrong on your end, then have no fear, it’s not a problem with your connection or router. Unfortunately, this is all down to something on the service side, which means waiting until developers Techland can roll out a fix.

The day one patch cleaned out 1000 or so bugs from the version of Dying Light 2 we got to review, but it would seem that this network connection issue managed to sneak past any attempts to clean it up. For now, all you can do is stay patient. It is not impossible to play coop with friends, it can just take some patience to get the connection up and running.

To prevent heartache, however, we would suggest holding off on the coop play until the developers have a chance to stabilize the service. It is also a good idea to follow Dying Light on Twitter for any updates from the developers about ongoing problems.