When you get a low-rated puzzle compared to your own puzzle rating you get small reward for solving it (like 5 points only) and big penalty (15 and more points) if you fail to solve it
Try "hard" or "extra hard" options to see if you start getting higher rated puzzles so that the reward and penalty would be more balanced
I just solved 5 puzzles correctly and got max 8 points for each. However for just one wrong puzzle after it, I lost 21. Is it fair??. Also is solving extra hard puzzles(new setting) gives u extra point or deduct less points?