This started last night. When I hit seller's other items for sale and more than one page of results show at the bottom i.e. 1, 2, 3 etc, a number of pages don't show up. For instance, for one seller with 18 pages, pages 5 and 16 showed 0 results. This morning for a seller with 3 pages of unique items, only page 1 showed. I seem to recall this being a recurring problem, but it's irritating for a buyer, and worse for a seller.
