Some of the cards might have already existed from a previous import - best way to avoid that would be to reimport them with "duplicate handling" set to "allow." (to be honest, for pedagogical reasons "fixed" is not something we generally try to encourage - with frequency lists like this we normally suggest that people break up the list into smaller categories (using the easy "split" feature accessible by long pressing on a category name) and add a new one whenever they run out of new cards in their existing ones)