Hi Kelly -- I'm sorry you are having an issue getting maps to appear in your story. Is it just this map or all maps? Can you add a map from the Living Atlas tab successfully?
We don't have any reports or see any signs of this being a common or widespread issue, so I'd recommend that you please contact Esri Technical Support and they can help you troubleshoot. This may be an issue with this map, your computer, or your network environment.
Owen Evans
Lead Product Engineer | StoryMaps