og:image issue with Facebook share

Hi,

we have an issue with FB sharing, because og:image property is set to:
http://yourdomain.com/components/com_easyblog/themes/wireframe/images/placeholder-image.png
See the real link shortened below
http://goo.gl/SBdYPK

This is checked with https://developers.facebook.com/tools/debug/og/object/

Pls let us know how can we include the image inserted into the post instead of this placeholder png file.

Many thanks