Custom field PHP pulling data from incorrect post

I have some custom field calls in the sidebar of my post pages which pull data from custom fields in the post. I have instances where some custom field calls are pulling data from other posts, not from the post that the sidebar is currently on. I think this is happening after I have blank custom fields, and then try to add data again. Though I haven’t been able to reliably recreate it in any instance.

Below is the code in my sidebar that I’m using to call the custom field data:

<?php
$sellerphone = get_post_meta($post->ID, 'sellerphone', true);
$sellermobilephone = get_post_meta($post->ID, 'sellermobilephone', true);

if ( $sellerphone || $selleraddr ) {
   _e('For questions <strong>about the property</strong>, please contact the seller:','language');?><br />
<?    if ( $sellerphone )
       echo 'Phone: ' . $sellerphone. '<br />';
      if ( $sellermobilephone )
       echo 'Mobile: ' . $sellermobilephone. '<br />';
?>

The website is being built on this theme: http://gorillathemes.com/real-agent-wordpress-real-estate-theme/. However, the custom fields I’m trying to call I added in myself based on how the rest of the custom fields were being handled in the theme. So if this isn’t a WordPress problem, it could very well have something to do with how I edited the theme. If that’s the case I’ll take the problem over to their forms.

Thanks for the help!