Weird Server Connection Issue

I recently moved, and post-moving I've been having a really weird connectivity issue. When I load one of my campaigns (campaigns that were working fine before the move), no one can connect to my server even though the connection test says its fine.

However, if I:
-Start the server,
-Immediately exit to launcher,
and then
-Start the server again,

Then suddenly people can connect.

Any idea what could be causing this?

It sounds like the port forwarding is not working correctly. FGC will attempt to auto-configure port forwarding using UPnP; but it may not work or be disabled on routers. You may need to set up the port forward rule directly on your router.

Regards,
JPG