Hi @burlingtonpress,
Thank you for your reply and continued patience.
If the button still shows, we believe that there might be a conflict preventing the indexing from completing. In order to troubleshoot, we want a bit more information about your site.
A) Are you running the latest WordPress 5.4.1? If not, can you please update and check whether the issue persists?
B) Are all plugins and themes up to date? If not, can you check if you click the button after installing all open updates works?
C) Does your site meets the plugin requirements found here: https://yoast.com/help/plugin-requirements/?
If all of the above is in place and your site meets the requirements, we would like you to run the indexing process in the troubleshooting mode of the Health Check plugin. This temporarily disables all plugins and switches to a default theme (only for your user, site visitors are not affected). In this mode, only activate Yoast SEO and go to SEO > Tools and click the Speed up my website button and check if it completes + if the checkmark then shows for you. You can find more information about the Health Check plugin here: https://yoast.com/help/how-to-check-for-plugin-conflicts/.