"Ok" missing in tincan Resume Dialogue Box

Hi,

I'm running Tincan content on a Learndash LMS. When a student goes to resume the tincan content the resume dialog box (pictured below) is missing the "OK". I have inspected the page using Google's Inspect tool to identify that the text "OK" is actually missing (that is it is not a text color css problem).

this problem is not new, it has been occuring for several years, with several versions of Captivate.

Any ideas on how I can reinsert the "Ok"?

Cheers,

Rob.