Unable to connect to Steam Game Server

[C00kieGamez]

Throws a "Connection was closed by peer, Timed out attempting to connect" when attempting to connect to a Mirror server running on a dedicated server running Steam Game Server and connecting via the server ID given by the Steam Game Server.

How to replicate:
Initialize Steam game server (in my case via heathen Steamworks Behaviour)
Run NetworkManager.StartServer() after Steam has initialized
Make dedicated server build and add steam_appid.txt to the build folder
Run the server and wait utill it initializes with "Game Server connected to Steamworks successfully"
Copy down the "Server ID"

Put "Server ID" inside the mirror NetworkManager Network Address field
Initialize Steam
Run NetworkManager.StartClient()
Console prints "Starting client [SteamSockets], target address 90199679415317530."
Console prints "Connection was closed by peer, Timed out attempting to connect"

all tested on steam_appid 480.

[kimlaya]

Yes, I can't do it either, I tried all the transports

[dylanpdx]

Having the same issue. Normal P2P works fine, but SGS gives a "Timed out" error