vanilla javascript and html 5 drag and drop API

I deployed this app without fixing the drag and drop API. The drag and drop really gave me a very hard time, i spend days trying to make it work but i still couldnt make it work 100%. I would be very glad if am given or redirected to an article that explains how to drag dynamically added elements. the way that have made the drag and drop work is that, am looping on all my li elements and adding the drag,dragover,drop event listener on them. Please help check my source code and tell me what am doing wrong or some other things i needed to do that am not doing. check the live preview site and see what is wrong. Thanks