Data vanished but still showing on my cloud browser

Hi there ive got a 2tb my cloud Ive just turned it on and all my data seems to have disappeared but when I load up the my cloud browser its still showing 3.6gb of pictures etc etc also my iTunes is still playing from the drive? any idea whats happened or how to get this data back visible on my computer? Ive since added data back to one of the shares but when I check properties its showing as 0 bytes?

What device are you using, Windows or Apple? How are you trying to view it? More info and images will help in trying to solve your problem.