I agree with Jim, something is bent, and that linkage is not simple, but it is all visible when you open it up. Your comments suggest you can make it work, it just not like it should be, if that is the case, experimenting with the linkage should solve your issue. Bottom line is I am guessing that if you can straighten the linkage, you will solve the problem. I think I may disconnect that linkage interlock with my brakes, it is more trouble than it is worth. Not sure how to do that yet.