I made this account to play with my brother on bo3 split screen and while I had it while a...

Have you tried changing any of the game setting?

I've had that problem once while playing split screen with my brother and we noticed that changing some of the game settings helped with our problem.

Hopefully this helps your situation.

As far as I know that is the way things work when you play split screen. I have never come across a game where a guest or a second account can talk while split screening.

We are having this same exact problem! Hubby joined my realm for the first time using split screen, played for a while. Then logged onto the realm on his own and it was if he had never played, all of his progress gone. Logs back on with me using split screen, and his previous progress is there. It's treating it as if it is two separate accounts.

i had this happen a while back contacted epic still havnt herd a word. the glitch is caused when playing split screen disconnected from live

I played one a while back with my cousin on split screen.

I can't remember which one it was though. The gameplay was fun at least.