Create new Wordpress post [wp_insert_post] based on results of a WP_Query

functions.php

add_filter('uwpqsf_result_tempt', 'customize_output', '', 4);
function customize_output($results , $arg, $id, $getdata ){
	 // The Query
            $apiclass = new uwpqsfprocess();
             $query = new WP_Query( $arg );
		ob_start();	$result = '';
			// The Loop

		if ( $query->have_posts() ) { ?>
        
        
      <div class="orderresult_range">
            
      <div class="range_title">
	  	<?php $terms_as_text = strip_tags( get_the_term_list( $query->post->ID, 'ranges', '', ', ', '' ) ); echo $terms_as_text;?>
      </div>
       
       
        <?php  
			$range_image = get_field('range_image', $query->ID);					
		?>
       
      <?php if( $range_image ): ?>
             	 <img src="<?php the_field('range_image');?>" width="186" height="182" />
             <?php else : ?>
  	           <img src="<?php bloginfo('template_url'); ?>/assets/img/tempimage.jpg" width="186" height="182" />
             <?php endif;?> 
       
      </div>
      
      
    
			<div class="orderresultholder_title">
            
            <table class="orderresult" width="100%" border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td>Code</td>
  </tr>
  <tr>
    <td>Carats</td>
  </tr>
  <tr>
    <td>Price</td>
  </tr>
  <tr>
    <td>Qty</td>
  </tr>
  <tr>
    <td></td>
  </tr>
</table>
            
            </div>
			
			
		<?php while ( $query->have_posts() ) {
				$query->the_post();  ?>
    
    
    		<div class="orderresultholder">
            
            <table class="orderresult" width="100%" border="0" cellspacing="0" cellpadding="0">
  <tr>
    <td><?php the_field('style_code');?></td>
  </tr>
  <tr>
    <td><?php $terms_as_text = strip_tags( get_the_term_list( $the_query->post->ID, 'sizes', '', ', ', '' ) ); echo $terms_as_text;?></td>
  </tr>
  <tr>
    <td><?php $sellprice = get_field('selling_price', $query->ID); echo "R ".number_format($sellprice, 0);?></td>
  </tr>
  <tr>
    <td>qty</td>
  </tr>
  <tr>
    <td>
    
     <?php  
		$order_productcode = get_field('product_code', $query->ID);
		$order_productdesc = get_field('product_description', $query->ID);
		$order_productcost = get_field('selling_price', $query->ID);
	 ?>
    
    
     <?php 
	if(isset($_POST['new_post']) == '1') {
    $post_title = $_POST['post_title'];

    $new_post = array(
	  	  'post_type'		=> 'order-items',
          'ID' 				=> '',
          'post_author'		=> $user->ID, 
          'post_title' 		=> $post_title,
          'post_status' 	=> 'publish'
        );

    $post_id = wp_insert_post($new_post);

	add_post_meta($post_id, 'linked_order_id', 379, true);
	add_post_meta($post_id, 'product_code', $order_productcode, true);
	add_post_meta($post_id, 'product_description', $order_productdesc, true);
	add_post_meta($post_id, 'quantity', '1', true);
	add_post_meta($post_id, 'unit_price', $order_productcost, true);

 // This will redirect you to the newly created post
    $post = get_post($post_id);
    wp_redirect($post->guid);
}      

?>      

<form method="post" action=""> 
    <input type="text" class="orderresult_qty" name="post_title" size="45" id="input-title"/>
    <input type="hidden" name="new_post" value="1"/> 
    <input class="subput round" type="submit" name="submit" value="Add"/>
</form>
    </td>
  </tr>
</table>
            
            </div>


		<?php	}
                        echo  $apiclass->ajax_pagination($arg['paged'],$query->max_num_pages, 4, $id, $getdata);
		 } else { ?>
         
         <?php 
					 echo  'no post found';
				} ?>
  

   
				
<?php

/* Restore original Post Data */
				wp_reset_postdata();

	$results = ob_get_clean();		
			return $results;
} ?>

I think that if statement have problem. try this once

if(isset($_POST['new_post']) && $_POST['new_post'] == '1')