I recently started the Microsoft learning track, whereby one creates an app by means of utilizing Azure, Github, node.js, npm and the Microsoft sandbox. After having followed all the instructions, the API won't seem to load in the web app although it loads when I accessed it locally through my web browser. I do understand that this is merely for learning purposes, although I like to do things right the first time. I have performed several commits, push and pulls to Github with very little success in loading the API from the preview URL. Please help.