All download links are not working after plugin upgrade

Hi, I am using Easy Digital Download plugin on my website GlobalScienceHeritage.org more then 8 or 9 years. I recently update the plugin and now download links are not working. I checked on wp-admin dashboard and found there is no file url added there but all download files are available in the media library. 

please help me in this case.

The page I need help with: [log in to see the link]

 

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