The Common Keywords you see in the report give a clue as to what’s actually going on:
You’re not actually running the SEO check on your website, you’re running the SEO check on the security page that’s presented to all visitors:
All of the SEO descriptions and headings and stuff not being found is not because they are not on your page, it’s because the scanner doesn’t actually check your page.
Don’t worry about the effect of this on SEO though. Actual search engine crawlers are a lot more sophisticated than any SEO checker.