@kkw7170
We’re really sorry to read about the issue you are experiencing.
Unfortunately, this relies mostly on the change in Google’s algorithm. Seeing a ranking drop may also occur due to a number of other factors. It could be related to a change of your site loading time, site structure, content quality, the competition of the search terms, losing rank of the particular search terms, etc.
Are you seeing any crawl errors in your Google Search Console report?
We also recommend you to read the following two articles on Yoast.com to learn more about how to find out what’s causing the drop and how to overcome this:
How to analyze a sudden drop in traffic
What to do if the traffic on your blog is decreasing?
Regarding the Pinterest title showing raw variables output on the title, we are not immediately sure if it’s due to our Yoast SEO plugin, we recommend updating all your active plugins and themes.
You might need to do a conflict check if still, the issue appears after updating (undo rollback) like before.
Often, we see problems occur in combination with another plugin or theme. The fastest way to rule out any conflict, is to deactivate all non-Yoast plugins and switch to a standard theme like Twenty Twenty.
Please test this on your development or staging site, if you have one. If not, we recommend using the Health Check & Troubleshooting plugin. This plugin has a troubleshooting mode, which does not affect normal visitors to your site.
If you’re unfamiliar with checking for conflicts, we’d like to point you to a step-by-step guide that will walk you through the process: How to check for plugin conflicts
If you do not feel comfortable to do this yourself or if this does not solve your issue, our Yoast SEO Premium plugin comes with one year of (technical) support.`