(UNET) ServerReturnToLobby() doesnt send my players back to the lobby?!

I've set my game up pretty much exactly like the networked tanks demo however when I call ServerReturnToLobby() from my static lobbymanager within my gamemanager I don't go back to my lobby scene, instead I get this "SetClientOwner m_ClientAuthortyOwner alreadyset!" . There isn't any clear indication of which NetworkIdentity is calling this, am I missing something? Do I need to override a specific function or are there any prerequisites when using the return to lobby function?

Any help would be greatly appreciated!

Thanks!