Do your posts not show up to all of your friends or only few of them?
If your post doesn't show up to all of them, see in settings if you have restricted your posts to yourselves only.
If it doesn't show to few of them, then this could be the reason:
Instagram doesn’t show every post to every follower. If your friend hasn’t interacted with your posts lately, Instagram may not prioritize your posts in their feed.
Ask your friends to go to your profile directly and check if the post appears. Tell 'em to like or comment more on your posts (to train the algorithm; sometimes it's algorithm you know.)
Also, make sure your friends (if few of them) haven't muted you
accidentally.