@goldnut: Have you checked the applicable CSV file available on your Star Seller page (previous period for September Star)? When you look at the file remember that that the dates / times are in UTC (not your time zone), only the first message of a new incoming thread is included (all that counts for Star Seller), and usually a new incoming thread is not included until after the 24 hour reply window has passed regardless of when you replied. Star Seller stats (and the CSV file) seem to be updated only once per day so there may be an additional day's delay. There is also a link to the actual message thread so you can verify if the data is correct or not.
Keep in mind that the Star Seller metric is NOT all new messages but only the first message of all new incoming threads.
If the unanswered new thread is not a Help Request, at least for the time being, it appears that marking an unanswered message as SPAM (even after the 24 hour deadline has passed) will cause your reply percentage to change in a day or two if the original message was within the current star seller period (but not retroactively). Note that subsequent messages from that account may go directly to the SPAM folder.
As mentioned above, even if Etsy Support or the Help Pages sent you here this is a seller peer to peer forum, and should not be considered a way to contact Etsy, if that is your hope (although Etsy does sometimes read and reply to posts).
