user data does not load reliably in multiplayer split screen

When playing multiplayer split screen with my kids the game does not remember their characters. They load in at the spawn point with just a starter map like they had never played. The only thing it saves is their skin. If I reload the map multiple times I can occasionally get lucky and their stuff will show up. Sometimes it happens to only one person, sometimes all additional players that join. I am the only one (player 1) that can reliably load. This is on the better together version.

Also, lots of game crashing and lag. Everyone is using their own gamertag ( no guests. ) All my software is current. I never had any issues with the old Xbox one version. Please let me know if there is anything I can try because this is truly game breaking and I would prefer to play this newer version as opposed to going back to the XB1 version.