Instagram API -在第一页上没有返回正确数量的图像

我需要feed一次提供7张图片。由于某种原因，除了第一页只提供5个外，所有页面都提供了7个。

<?php
function fetchData($url){
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_TIMEOUT, 20);
    $result = curl_exec($ch);
    curl_close($ch); 
    return $result;
}
$maxtagid = (isset($_GET['instatag'])) ? $_GET['instatag'] : false;
$url = "https://api.instagram.com/v1/users/self/feed?access_token=$accesstoken&count=7";
if($maxtagid){
    $url .= "&max_id=$maxtagid";
}
$result = json_decode(fetchData($url)); 
foreach ($result->data as $post) echo '<div class="insta-square"><a target="_blank" href="'.$post->link.'"><img src="'.$post->images->standard_resolution->url.'" alt="'.$post->caption->text.'" width="100%" height="auto" /></a></div>';
$nextmax = $result->pagination->next_max_id;
if($nextmax != ''){ ?>
    <div class="insta-square"><a href="<?php echo get_home_url(); ?>/gallery?instatag=<?php echo $nextmax; ?>"><img src="<?php echo get_template_directory_uri(); ?>/images/next-slide-square.png" /></a></div>
<?php } ?>

我已经玩了各种设置，如果$maxtagid设置，删除VERIFYPEER等，似乎没有工作。我做错了什么?