The update to EndNote 20.0.1 will resolve the issue. Please update your copy of EndNote.
https://support.clarivate.com/Endnote/s/article/EndNote-20-Release-Notes?language=en_US
https://support.clarivate.com/Endnote/s/article/EndNote-20-Updates?language=en_US
If you continue to have an issue after updating EndNote then please contact Technical Support directly:
1-800-336-4474 option 4 then 1
or