Can’t make groups more than 312

I have a meta box with cloneable field, but it limited to only 312 item. Whenever I tried to clone more than that, it reset to 312. Here is my meta box code:

` $meta_boxes[] = array(
‘title’ => ‘Link CDN’,
‘pages’ => array( ‘anime’ ),
‘tabs’ => array(
‘input-version’ => array(
‘label’ => ‘Input LINK CDN’,
‘icon’ => ‘dashicons-admin-customizer’,
),
),
‘tab_style’ => ‘default’,
‘fields’ => array(
array(
‘id’ => ‘ab_cdngroup’,
‘type’ => ‘group’,
‘max_clone’ => 0,
‘clone’ => true,
‘sort_clone’ => true,
‘save_state’ => true,
‘desc’ => ‘<b style=”color:red;”>Masukkan Link CDN</b>’,
‘tab’ => ‘input-version’,
‘fields’ => array(
array(
‘name’ => ‘Nama Episode’,
‘id’ => ‘ab_namaep’,
‘type’ => ‘text’,
),
array(
‘name’ => ‘Link CDN’,
‘id’ => ‘ab_linkcdn’,
‘type’ => ‘textarea’,
‘sanitize_callback’ => ‘none’,
),
), //episode
), //input-version
),
);

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