Except the person replied to a sticky that I had not closed. So it will not move by itself. His post was completely different from my sticky. I think all I can do is close the sticky. Delete his post, and re-create it under my username.
I also have a sticky user’s guide, and added this wording:
To start a new thread or topic, click on the Start New Topic Here link in the “Latest Discussions” section.
Advantage to Starting a New Topic:
You Topic Heading will show up in Latest Discussions!
Disadvantage to Replying to an Existing Topic:
If your reply has no relevance to an existing topic, it will not feature prominence in “Latest Discussions”. But please feel free to reply to an existing topic , if it is relevant to the existing topic.