Soft 404 Errors: need help deciphering URLs from Google Search Console

Hi,
Our Google Webmaster tools Search Console says that we are getting loads of “Soft 404” errors. It lists URLs that I can’t decipher at all. I can’t figure out where
google is finding these URLs in our site, or what might be generating them.

And I

Hoping that someone can point me in the right direction. The URLs look like this:

https://www.councilofindustry.org/wp-admin/admin-ajax.php?action=PopupBox&current_view=0&fb_id=1&theme_id=1&open_with_fullscreen=0&open_with_autoplay=0&image_width=800&image_height=600&image_effect=fade&enable_image_filmstrip=0&image_filmstrip_height=70&enable_comments=1&enable_likes=1&enable_shares=1&enable_author=1&enable_name=1&enable_place_name=1&enable_message_desc=1&enable_image_ctrl_btn=1&enable_image_fullscreen=1&enable_object_info=0&slideshow_interval=5&enable_image_facebook=0&enable_image_twitter=0&enable_image_google=0&current_url=name%3D3d-printing-goes-hollywood&image_id=137&image_id=

And that URL simply gives the error message “The image has been deleted.” No 404 error message or anything like that.

I’m guessing that it was generated by the blog post here:
https://www.councilofindustry.org/3d-printing-goes-hollywood/

And guessing(?) that perhaps(!?) it comes from the AddToAny sharing plugin, which does pop up a modal window…

Why are we seeing these errors?
What can I do to have those directed to a proper 404 error page?

ANY suggestions that might lead me in the right direction would be helpful!

Thanks!

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