4 man squad - 1 players get kicked out

Hello
We play as 4 - 3steam and 1 xbox.
We are together in the same squad, the first game is fine, but when the game is over and the matchmaking restart(without exiting), we find a game, but the xbox player does not find this game and he is geeting kicked out.
We need to return to the menu in order and restart the matchmaking as 4.

Any idea on why ? 

Thanks