I have had the problem of my left shoulder going forward for a while now. My instructor and I found out that it stemmed from having my left heel jammed forward. Well, I fixed that problem but my left shoulder still drifts forward and its really hard to get back where it supposed be and as soon as I am not 100% focused on it, it goes forward again. It also gets alot worse when I am jumping. Can I please have some tips to fix this problem? Its putting me and the horse off balance.