The best way to fix this, do the following: 
  1. Select the Data Element that you want to fix on the right-hand side 
  2. Click < Remove. 
  3. Highlight the element that was above that Data Element on the right-hand side. 
  4. Select the Data Element that you just removed on the left-hand side. 
  5. Click Add >. 
  6. Select the Data Element that you just re-added on the right-hand side. 
  7. Click Save Order and Edit Selected. 
You should now be able to see the fields for that Data Element under Edit Data Element at the bottom.