php中的bootstrap折叠foreach循环

我很难使用带有Bootstrap collapse的foreach语句。每次我点击最后一个或第一个面板时，它总是打开一个不同的面板，而不是它自己，并折叠一个不同面板。

<?php 
    $x = 0;
    foreach($infos as $info): 
?>
<form action="../../Core/init.php" method="POST">
    <div class="panel-group" id="accordion" role="tablist" aria-multiselectable="true">
      <div class="panel panel-default" role="tab" id="heading<?php echo $x; ?>">
        <div class="panel-heading" >
          <h4 class="panel-title">
            <a role="button" data-toggle="collapse" data-parent="#accordion" href="#collapse<?php echo $x; ?>" aria-expanded="false" aria-controls="collapse<?php echo $x; ?>">
                <?php echo strtoupper($fname); ?>
            </a>
          </h4>
        </div>
        <div id="collapse<?php echo $x; ?>" class="panel-collapse <?php echo ($x == 0 ? 'collapse in' : 'collapse'); ?>" role="tabpanel" aria-labelledby="heading<?php echo $x; ?>">
          <div class="panel-body">
                <div class="form-group">
                  <label class="control-label" for="inputWarning"> Name</label>
                  <input type="text" class="form-control" value="<?php echo $name; ?>" readonly>
                </div>
                <div class="form-group">
                  <label class="control-label">Age</label>
                  <input type="text" class="form-control" value="<?php echo $age; ?>" readonly>
                </div>
                <div class="form-group">
                    <label class="control-label"></label>
                    <textarea class="form-control" rows="6" id="textArea" name="message" maxlength="1000"></textarea>
                </div>
                <button class="btn btn-block btn-lg btn-danger" name="message" >Submit</button>
          </div>
        </div>
      </div>
    </div>
</form>
<?php $x++; endforeach;?>