Wrong Image using Facebook Share

Hi,

Thanks for replying. I figured that out. I put meta tag in wp_head.

function insert_meta_tag_in_head() {
 global $post;

  if(!has_post_thumbnail( $post‐>ID )) {

  $default_image='<img src="http://placehold.it/780x400?text=[img]';
    echo '<meta property="og:image" content="'.$default_image . '"/>';
  }
  else{

   $thumbnail_src = wp_get_attachment_image_src( get_post_thumbnail_id( $post‐>ID ), 'small' );
   echo '<meta property="og:image" content="'.esc_attr( $thumbnail_src[0] ).'"/>';
  }
}

add_action('wp_head','insert_meta_tag_in_head');

This is resolved already.

Thanks,
Abner