As an admin, you can delete users tracked in Canny via the Users page:
You can also permanently ban a user from being able to ever post on your Canny Board again. We only recommend using this option if there have been clear abuse/spam concerns. Marking a post/comment as spam will also delete and ban the author.
When you delete a user, you will remove their:
Posts that have no votes or comments (we will keep posts open that have vote/comments from other users)