php - is_user_logged_in not working in premiumpress theme -

i'm having problem function_is_user_logged_in. can seen on http://dev.cellarsale.co.za/index.php/listing/example-listing-2/ . i'm trying make "buy now" line disappear unlogged people.

it's not working on website part of code :

ob_start();  (...)  <table> <tbody> (...)  <?php if(is_user_logged_in()){ ?>       <tr id="buynow" style="display: none;">      <td colspan="5" class="bidbox biddingbox">       <div class="wrap">      <span class="label label-default pull-right" onclick="jquery('.biddingbox').hide();" ><?php echo $core->_e(array('account','48')); ?></span>       <hr />      <form method="post" action="" class="row clearfix" onsubmit="return checkbidding();">     <input type="hidden" name="auction_action" value="newbid" />     <input type="hidden" name="bidtype" value="bid" />     <input type='hidden' name='hidden_cp' id='hidden_cp' value='<?php echo $current_price; ?>' />       <div class="col-md-4">      <div class="txtb"><?php echo $core->_e(array('auction','89')); ?></div>      </div>      <div class="col-md-4">                  <div class='input-group'>         <input type='text' class='form-control' id='bid_amount' name="bidamount"  placeholder='<?php echo ($current_price+1); ?>' />          <span class='input-group-addon'><?php echo $globals['core_theme']['currency']['symbol']; ?></span>         </div>               </div>             <div class="col-md-2">                 <button class="btn btn-lg btn-primary" type="submit"><?php echo $core->_e(array('auction','66')); ?></button>             </div>      </form>      <script>     function checkbidding(){             <?php       if($userdata->id && ($userdata->id == $post->post_author && $userdata->id != 1) ){ ?>       alert("<?php echo $core->_e(array('auction','72','flag_noedit')); ?>"); return false;       <?php }elseif($userdata->id){ ?>          var bidprice = jquery('#bid_amount').val();         var ecp = jquery('#hidden_cp').val();            var ecp = math.round(parsefloat(ecp)*100)/100;         var bidprice = math.round(parsefloat(bidprice)*100)/100;          if(jquery.isnumeric(bidprice) && bidprice > ecp){                return true;         }else{         alert('<?php echo $core->_e(array('auction','73','flag_noedit')).' '.$globals['core_theme']['currency']['symbol']; ?>'+ecp+'');         return false;         }      <?php }else{ ?>          alert("<?php echo $core->_e(array('auction','56','flag_noedit')); ?>"); return false;      <?php } ?>      };     </script>      <hr />      <h4><?php echo $core->_e(array('auction','20')); ?></h4>      <?php echo $core->_e(array('auction','90')); ?>      <hr />     <p><?php echo $core->_e(array('auction','65')); ?></p>      <textarea><?php echo stripslashes($globals['core_theme']['auction_terms']); ?></textarea>       </div>      </td>     </tr>             <?php } ?>  <?php } ?>             </tbody> </table>  <?php  // return output $output = ob_get_contents(); ob_end_clean(); return $output; 

i think ob_start() @ beginning might reason why it's not working thing used is_user_logged_in above , worked. tried put content in "if(is_userlogged_in)" : still working first part not 1 above.

i tried @ 1 point hide css check using code below:

it didn't work @ all, logged or unlogged people.

does has ideas please ?