According to the log, your network connection to the server died. This isn't something OBS is doing, or can fix.
You can try restarting your modem/router, that can correct network drop-outs sometimes... many 'home routers' do not have good support for long-persistence high-throughput connections, and can 'fall over' internally with their TCP handling stack if too much traffic goes through without any kind of break or reset of the connection (and livestreaming does exactly that, by necessity) when they haven't been rebooted in a while.
Beyond that... well. There's a lot of stuff that can cause it, and tracking that down goes pretty far beyond the scope of OBS support, as it comes down to troubleshooting your network connection itself, and in-depth.