We understand that the Yoast SEO plugin disappeared for you unexpectedly and you have removed the wordpress-seo
folder directly from the /wp-content/plugins
directory of your WordPress installation but you’re still experiencing the issue “destination folder already exists” issue.
If you’re still unable to upload the Yoast SEO plugin through your site dashboard plugins page due to the “destination folder already exists” issue, it clearly means the wordpress-seo
folder still exists on the /wp-content/plugins
directory on your server where WordPress is currently installed.
So, you’ll need to remove the relevant folder first before you could re-upload Yoast SEO on your site again. We have a step-by-step guide here that will walk you through the entire process: https://yoast.com/help/common-installation-update-errors/