Check if your issue is https://codeberg.org/Kbin/kbin-core/issues/1019
the last few posts to this magazine have all been people saying they can't view posts / comments when logged in but can when logged out (which you might not be able to see of course if it is this issue, as they were all posts and not links). Try removing all blocked domains to see if you can see them again.
Edit: To be clear, this is to fix being able to see the posts after the error, not fixing the error. My current working theory is:
users on kbin.social get an error when posting. the post is made, but with an empty domain field
kbin.social users with any domains blocked, regardless of what they are, will not be able to see the post or comments if they open the post via url
McBinary
VulcanSphere