Why am I unable to join a party in Fortnite?

We are aware that some players could not join their friend's party in Fortnite, and with the recent patch, this was fixed.

If you are still encountering this issue and you or your friend are playing on Xbox, then please make sure invites are allowed on your console and your friend's console by following the instructions in "Why are my friends unable to join my party in Fortnite on Xbox?"