Original Post — Direct link

They have removed an important feature, the "Non-Friend Whisper". Now random people can walk up to me and invite me to a party, (why is this a feature), you should at least force them to "friend" me first before they can do this, or better yet, talk to me first (hopefully to explain why they need me for the party). I can only "Accept" or "Decline", I can not "Whisper" to them to ask them what it is that they are trying to do, or even what level they are. This is stupid, I am not going to join somebody's party just so I can find out the reason why they asked me to join their party. So, if you are a person that randomly asks people to join their party, at least try to tell the person what you want help with before sending the party invite. I don't accept random party requests without this information.

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26 days ago - /u/joshlhood - Direct link

Unfortunately this is something out of our control - our social/messaging/friends system is based on the Epic Games one, and they no longer support messaging a player not on your friends list.

It may not fully solve your case here, but you are able to block Party invites from non-friends in the Options > Gameplay screen if you'd prefer to do so.