Empty worlds render two suns at daytime instead of one sun and one moon

In the empty worlds supposedly should have a sun and a moon. And so
overnight (https://gyazo.com/1f4b40a4b3020cf175eee35b6656fb53). But by day two suns and should have one. (https://gyazo.com/35ba6789dca42d068a999aeac46aace0)