This puzzle has a condition which requires at least five hydrogen bonds. Hydrogen bonds are shown as blue-and-white "candy canes" or spirals.
When the puzzle starts, there are only two hydrogen bonds, and the condition is applying a 2000 point penalty.
You can drag on parts of the protein to move them around, making or breaking hydrogen bonds.
Try dragging the lower sheet toward the upper sheet until you have five hydrogen bonds. It may be easier to rotate the protein by dragging on the background before you try dragging on the sheets.
When you have at least five bonds, the 2000 point penalty becomes a 2000 point bonus, and the puzzle is completed.
If you're having trouble, try resetting the puzzle. On the next try, rotate the protein by dragging on the background to make it easier to line up the sheets as you drag them.