Are you using the auction format? For auctions, you can list for up to a maximum of 10 days. It wouldn t make much sense to have a 30 day auction; no one would want to be bidding for month.For fixed-priced items you can list up to 30 days, and for store inventory you can list for 30 days or Good Til Cancelled.
when you list an item, the default days of listing is 7. there s a box option that gives you 3, 7, 30 or unlimited. the unlimited one will recycle itself if you want it to recycle itself or if your item has not sold.
fixed price/buy now items DO have 30 day listings - regular auction listings are 10 days max