@KadiesCollectibles: Did Etsy Support or the Help Pages send 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).
Probably almost everyone on this forum can sympathize with you but a quick search would show you innumerable threads about your exact issue. As it says right on your Star Seller page, you need to reply to the FIRST message of a NEW INCOMING THREAD.
It does not matter who sent it, the subject matter, if it is a duplicate or blank or anything else. If it is SPAM then it should be marked as such. Those have always been the rules.
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.
