please help me!!

All the letters fall down if Ты make a mistake - if it's happening even though Ты haven't made a mistake, it may just be that the game is glitching.
During the beta trial they had a ton of problems with the dueling and it was shut down for over a month.

To play properly Ты have to either click on the letters или press them on your keyboard at the right time (as the white line hits the Далее letter). To gain power Ты want to click или press the letter just as the white круг swells to it's largest size around the letter. Keep practicing, you'll get it!