Facebook sharing meta doesn’t show properly as the preview shows

Hello,

Please, look at the first screenshot. This is my single post meta settings. The post title and the post excerpt. Yeah, everything is alright here.
Now please look at the second screenshot. This is the Facebook sharing meta preview. The post title and the post excerpt are also shown here. It’s also alright.

But now look at the third screenshot. This is the result! This is shown when I share a post on Facebook! Where is the post excerpt? And why is appearing my site title here?

What’s the issue? Please tell me how to fix it?

Thanks…