Multiplayer on 2 xboxes with family

Hi there.
A while ago we bought the special Forza Motorsport 6 xbox.

We now have a second xbox one and my better half and I wish to race using the online multiplayer.

I can log in and set up a race.
On thensecond xbox however she periodically keeps beeing booted out and asked to purchase the game.

I have to log my account back in. Then change accounts to hers.

Is this a bug or do we need to have a second copy of the game. Even though she accesses it no problem as a family member playing solo.

Thank you kindly in advance for the replies.

Set the console that she is playing on as your home console and you should be able play against each other no issues
Xbox live will be shared as well

So set both consoles as home?

You can’t set both as your home
You play on your console…and set the one she plays on as your home console

Ok, I’ve just done that but now I can’t launch the game and it’s asking her if she owns the game and if so to insert the disc.

Are you connected to online with both consoles when doing this
You do own it digitally don’t you ( your account) and it is still installed on both consoles