I decided to wait until the walkthrough was finished before I skipped. The game says they must be the same size, color, and same shape.
The walkthrough says you just need the same shape. The color doesn't matter. Yay! The puzzle was easy using different colors. If anyone else has this problem, you can let them know. I have more of the game left than I thought. I've enjoyed the game so far, but haven't had the problems some have had.