Why isn't my furnace type sorter working?

So I just recently built an XP furnace system that also sorts items put in. Each item then goes to their respective furnace, smoker, blast furnace. If I understand correctly, I need to fill 4 of the hopper slots with named items and the 5th slot with the item I want to pass through. I did this to the first hopper and had no problems, however the second hopper allowed the named items to pass through to the furnace… What am I doing wrong?