Hori Real Arcade Pro stick problem

ok... last night I noticed that I could not crouch block like I'm supposed to be able to do. so it seems I have a problem with the '1' position on my stick. I imagine this should be fixable, but my question is how do I fix this? and do I need new parts? and if so, what are they and where should I get them?

Any info/help/advice is greatly appreciated