Can’t fix: ‘og:image’ property should be explicitly provided, even if a value can be inferred from other tags

In short, you should re-fetch your website information using this tool:
https://developers.facebook.com/tools/debug/

Paste your URL and press Debug. Then either do Fetch, or press Scrape Again.
This will refresh Facebook cache, and your html-page will be reloaded.

Some additional info: https://stackoverflow.com/a/44453472/4899346