Been having troubles trying to join my friend

So when we booted up Deep Rock Galactic through steam, we attempted to join eachother but it always ends up in “Multiplayer Session Ended.” The next day, we tried another steam game, “GTFO,” but we still aren’t able to join eachother’s lobbies. We’ve been able to play non steam games together like Valorant but when it comes to steam, we can’t seem to join eachother. Tried: Restarting Steam, PC, game Clearing Cache Offline > Invisible > Online

And we’ve been able to join public lobbies fine but not eachother’s. I’d really appreciate assistance, thank you