Problem migrating Scalar book from one Reclaim site to another

Hello-
I am trying to migrate this Scalar book on another Reclaim site:
http://bongiov.com/scalar/massive-resistance/

To my Scalar installation on my Reclaim site:
https://lucycarrjones.com/scalar/massive-resistance/index

When I try to do it through the Import URL, I get this error:

There was an error resolving the Save API URL

I have also tried downloading the RDF-JSON file from the original site and uploading it but am getting the same error message.

Can anyone assist me with this?

Thank you!!