Content not save HTML

Hi
This is my code

<?php 
$form = '[mb_frontend_form id="gestione_prodotti_ok" post_fields="title, content, thumbnail" post_id="'.$_GET[pid].'"]';
echo do_shortcode( $form );
?>

...

    $meta_boxes[] = array(
        'id'         => 'gestione_prodotti_ok',
        'title'      => __( 'Gestione Prodotti', 'textdomain' ),
        'post_types' => array( 'prodotti' ),
        'context'    => 'normal',
        'priority'   => 'high',
		'fields' => array(
			array(
				'name' => __( 'Categorie', 'textdomain' ),
				'id'   => 'categorie_prodotti2',
				'type' => 'select',
				'options' => $myarray
			),
			array(
				'id' => $prefix . 'tag_prodotti',
				'type' => 'text',
				'name' => esc_html__( 'Tag', 'metabox-online-generator' ),
				'desc' => esc_html__( 'Separate values by comma', 'metabox-online-generator' ),
				'placeholder' => esc_html__( 'Separate values by comma', 'metabox-online-generator' ),
			),
			
		),
        
    );
    // 2nd meta box
    
    return $meta_boxes;

Where $myarray is a custom function.

Content field show wysiwyg editor, but if i add a media or put some style (bold, italic etc..) and save, "content" lose everything and save only text.
I want to preserve the html.
Can you help me?