It the “sort” you tried to sort by actually a field? If so, you would have to rename it, see this post.
If you wanted to sort by the usual sort oder if the numbered folders, you would not need to sort your pages at all because that is the default sort order anyway; if you wanted to reverse the standard sort order, you could just use flip().
But anyway, seems you have changed your mind and are sorting by date now, so I consider this topic solved?