You're banned, which means everything you post will be marked as "Dead". Only those with "showdead" enabled in their profile will be able to see your comments and posts. Others can "vouch" for your post to make it not "dead" so it can be replied to (which is what I have done)
As for why you were banned: https://news.ycombinator.com/item?id=30275804
Odd, I see his comment and I'm playing HN with undeads off ("showdead" is "no").
I had to vouch for the comment (make it not dead) to reply to it
Oh I see, you're playing medic.
Thanks, I always wondered what "showdead" meant (tho not enough to Google it I guess).