FIX: You could set reply_to_post_number when replying as a new topic

lib/post_creator.rb

@@ -56,6 +56,8 @@ class PostCreator
     @opts = opts || {}
     opts[:title] = pg_clean_up(opts[:title]) if opts[:title] && opts[:title].include?("\u0000")
     opts[:raw] = pg_clean_up(opts[:raw]) if opts[:raw] && opts[:raw].include?("\u0000")
+    opts.delete(:reply_to_post_number) unless opts[:topic_id]
+
     @spam = false
   end