Open File header.php

File Path: wp-content/themes/beetube/header.php

Line Number: 36

You will see this code.
<?php jtheme_meta_description($post_id); ?>

Add this code after this.

<meta property="og:type" content="video" />  
<meta property="og:image" content="<?php $image_id = get_post_thumbnail_id();
$image_url = wp_get_attachment_image_src($image_id,'small', true);
echo $image_url[0];  ?>"/>

Update file and problem is solved.