“无法找到没有ID的用户”ActiveRecord错误和编辑问题

So I am having some trouble with my rails app and I think I went a little out of my own depth. I am creating a simple alumni application and I want users to be able to join organizations. For some reason in my new join page I get the error "Couldn't find User without an ID". I want to know why the ID isn't passing in, which would imply signed_in? = false. I don't know why everything worked find when I created other additions to my users controller but here it refuses to take on the logged in user id. I feel like I am missing something simple, let me know if updates are necessary!So I am having some trouble with my rails app a