If we could actually work this out and troubleshoot it, that would be really good but we mostly have these things thrown out in isolation without much follow-up. Did you start playing connected, then lose connection?
Because what I know from first hand experience having done it last night is: Turning on flight mode, booting DOOM, clicking OKAY on the "yo, no online features that don't actually exist" message, and then starting a session went flawlessly without interruptions.
What is your setup, did you start connected? Like, let's actually figure out what's happening.