title: add_post_meta Multi value not working when i try to add them using loop
body: <p>At WordPress, I use a loop to add multiple meta values at a meta field. But every time it adds the lat value.</p>
  
  <p>Here is my code:</p>
  
  <pre><code>$value = array("red", "green", "yellow")
  foreach ( $value as $item ) {
      add_post_meta( $post_id, "_color", $item );
  }
  </code></pre>
  
  <p>Every time after saving it save only yellow.</p>
  
  <p>NOTE: This code works on my server but when I try to a client-server, it is behaving like this.</p>
  
  <p>Wordpress Version: 4.7</p>
  
  <p>Please help me.</p>