Yoast SEO Meta description missing with 3.03
Older version have issue
In the Yoast module you now need to use the Snippit Editor located at the top. If you hover the mouse in the right hand end of each field (page/post title, slug, meta description) you’ll see one of those pencil icons appear. Click on it and the field becomes editable.
Not a very intuitive change is the general consensus.
Solution : Just Update it to latest Yoast Plugin