Joining a Friends Party Disconnect

Everytime I try to join my brothers party or he tries to join mine we get disconnected within minutes and have to wait for Borderlands 3 to Reconnect to the internet (The internet never went down). We are on the same connection via Ethernet. We simply cannot play. I’ve seen similar issues but no fixes. I’ve heard random matchmaking works fine but I am unable to properly play more than 5 minutes at a time with someone physically in the same room on a different PC. But we can play simultaneously as long as we don’t play together. It’s infuriating and making me regret our purchase and If I was vindictive I would get my money back as the game was purchased twice simply for this feature. Fix this now screw nerfs and buffs let me play with my friends.