My unicycle cotterless crank is loose

http://i304.photobucket.com/albums/n...P1070367-1.jpg
--- There's a picture of my left crank which adjusts side to side
when it's not supposed to. Whenever I try to tighten the black wheel
thing inside of the left crank it still moves slightly side to side. I
also noticed that when I compared the right and left crank there was a
hole in the middle of the left crank (the one that needs fixing) and
no hole on the right crank. Is it supposed to be like that and if not
what piece am I missing?