Importing slide video captions issues

I have a captivate 2017 project with a single slide video.  I have created captions for the video within the video timing.

I needed to update the video with a new version and have exported the closed captions for the old video. 

How do i import the closed captions for the new updated video?  The option to import is grayed out in the drop down menu.

Having to redo all of my captions when i update a video file seems completely counter productive.