Hi,
We can see for this url: rivenfield.se/2017/08/26/1a-pris-pa-vart-andra-b-jaktprov-nkl-i-ludvika/ that the og: description tag is not outputting the right data: https://pasteboard.co/GPcZQsw.png
That sounds like a plugin or theme conflict. Can you try and gather as much information for us as possible? Please perform the following:
1. Clear all your caching from your plugins/theme/server/browser/CDN (such as CloudFlare).?
2. Check for conflicts using this guide: https://kb.yoast.com/kb/how-to-check-for-plugin-conflicts?
3. Check for JavaScript errors with your console on that page with this guide: https://kb.yoast.com/kb/how-to-find-javascript-errors-with-your-browsers-console
If you find any JavaScript errors related to Yoast SEO or if there is a conflict with a plugin or a theme, you can create a new GitHub issue here: https://github.com/Yoast/wordpress-seo/issues/ for our developers. Please report the issue to a third party developer as well.
If you didn’t find any conflicts or errors, we think the issue is specific to your site. We’d need to investigate further but are unable to do so on these forums. You can purchase Yoast SEO Premium here: https://yoast.com/wordpress/plugins/seo/ and receive our Premium email support and we can help you further.