http://www.newsweek.com/fortnite-xbox-one-crashing-freezing-not-working-60-patch-epic-1141471

Fortnite players on Xbox One are having trouble launching the game after installing Thursday’s 6.0 Season 6 update. Epic has responded to reports via an official tweet, but there is no fix available at the time of publish.

We are investigating an increase in crashes on Xbox. We'll provide an update once we have more information.