WordPress comments not showing with Socialcomments plugin

Hi,
i am using the social comments plugin and if i use this the wordpress comments are not showing up.
I checked in debugging mode and found this:

Notice: Undefined variable: post in /wp-content/themes/point/comments.php on line 27

Notice: Trying to get property of non-object in /wp-content/themes/point/comments.php on line 27

Notice: Undefined variable: post in /wp-content/themes/point/comments.php on line 34

Notice: Trying to get property of non-object in /wp-content/themes/point/comments.php on line 34

———————————————-
this are the code lines of the mentioned comments.php file line 26 to 35

<?php else : // this is displayed if there are no comments so far ?>
<?php if (‘open’ == $post->comment_status) : ?>
<!– If comments are open, but there are no comments. –>
<?php else : // comments are closed ?>
<!– If comments are closed. –>
<p class=”nocomments”></p>
<?php endif; ?>
<?php endif; ?>
<?php if (‘open’ == $post->comment_status) : ?>
<div class=”bordersperator2″></div>

Can the dev help me to sort this issue?