https://www.gamespot.com/articles/e3-2018-fortnite-switch-runs-into-problems-right-a/1100-6459763/

Fortnite was announced for Nintendo Switch during the Nintendo E3 2018 briefing, and it was released immediately after the event. The launch hasn't gone entirely to plan, however. [Update: It seems the problems have been resolved, and we've been able to play online. You can check out a new gameplay video above.]

In a tweet, developer Epic Games said it's looking into problems with matchmaking on Switch. Thankfully, there is a temporary workaround--logging out and back in. Hopefully a more permanent solution becomes available soon.