Only the friends you selected will be able to see your snap story.
If you choose 'friends', then only the specific people you have marked as friends in your settings will have access to view your snap story. No one else will be able to see it.
Maybe your friends set their stories to private and didn't include you. Or there could be a glitch in the app.
Maybe your friend has restricted the visibility of their story to certain people and you're not on that list.
Maybe your internet connection is bad. Check if your Wi-Fi or data is working properly.
Maybe your internet connection is bad. Try resetting your router or connecting to a different network.
Maybe it's a glitch in the app. Sometimes these things happen and it might get fixed after a while.
Maybe there's a problem with your internet connection. Check if it's stable.
Maybe your friends have restricted who can view their stories, or there could be a glitch in the app.
Maybe your friend has set their story to be visible to only specific people and you're not on that list.
Check your friend's privacy settings. Maybe they have changed it so that only certain people can see their story. Also, make sure your Snapchat is working properly. Update it if there's an available update. And check your network connection as a bad connection can also cause this issue.
Sorry, you usually can't see who took a screenshot of your Snap story. It's not a feature provided by Snapchat.