Sorry you are experiencing this problem.
I would just like to ask a few question to help identify the problem and hopefully be able to provide a solution.
1) What device are you using? (PC/Laptop, Tablet, Smartphone)
2)What Operating System? (Windows XP/Vista/7, Mac, Ubuntu, Android, Iphone)
3) What browser are you using (Internet Explorer, Mozilla Firefox, Google Chrome, Apple Safari)
Regards
Hydra
I have been having problems with the tactics trainer in that when I make my move, the piece moves, but the clock continues and the 'opponent' doesn't react. Only when I make the 'opponent's move (why can I move the opponents pieces??) does the clock stop and i get a fail! This happens about 30% of the time