I have a student who created a Story Map for a contest and she is getting this message when she tries to open it.
She deleted some older maps and might have deleted maps to build her Story Map. Is there a way to get all her hard work back?
How was the data published? Was it published through ArcGIS Desktop or was it just loaded as a layer in AGOL?
However, take a look at AGOL Assistant:
ArcGIS Online Assistant
This is a way to get into the JSON of your story map and see what links may supposed to be there (and possible a way to repair broken links).
Than you, I will try it.
Retrieving data ...