Graphs are blank when dashboard is delivered by email

Always the same 4 graphs are blank. I have tried both scheduling delivery directly from the Robots template and from a copy of the Robots template I saved to my dashboard. I should mention that the titles are displayed in the otherwise empty tiles.

I tried emailing other template dashboards with the following results:

Business ROI: Tile 3 has only the title, remaining 5 tiles are fine.

Processes: Tile 1 has only the title, remaining 4 tiles are fine.

Thank you,

Samantha