Unable to hit hook with form submit build with “wp_ajax_{$action}”

I’m all I’m currently trying to build a hook using do_action( "wp_ajax_{$ action}" ) on a Form submit. I built the following form.

 <div class="layout-gutter bg-grey-lightest p-4">       <div class="bg-grey-light p-4">         <form action="http://localhost:8080/wp-admin/admin-ajax.php" method="post">           <input name="action" type="hidden" value="feedback">           <?php wp_nonce_field( 'feedback_nonce' ); ?>            <fieldset class="c-question">             <legend class="c-question__label">Was this page helpful?</legend>             <div class="c-question__container">               <div>                 <label class="toggle">                   <input data-type="boolean" name="helpful" type="radio" value="1" />                   <span class="toggle__label">Yes</span>                 </label>                 <label class="toggle">                   <input checked="true" data-type="boolean" name="helpful" type="radio" value="0" />                   <span class="toggle__label">No</span>                 </label>               </div>             </div>           </fieldset>             <div class="c-question">             <label class="c-question__label" for="client-0-email-address">Why or why not?</label>             <div class="c-question__container">               <div>                 <input required="true" type="text" name="description" />               </div>             </div>           </div>            <div>             <button class="btn text-inherit" type="cancel">Cancel</button>             <button class="btn-primary" type="submit">Submit</button>           </div>         </form>       </div>     </div> 

But when I submit the form I am unable to hit the action hook. I have the following file lib/feedback.php

<?php namespace FeedbackNYC;  add_action('wp_ajax_feedback', 'FeedbackNYC\feedbackHandler'); add_action('wp_ajax_nopriv_feedback', 'FeedbackNYC\feedbackHandler');  function feedbackHandler() {   echo "Hellow World";   echo $  _POST:   // Do some code here } 

But when I submit the form I’m not getting to feedbackHandler. The form has a hidden input field <input name="action" type="hidden" value="feedback"> but I never get to the hook. I tried echo in strings but nothing gets returned back. The request returns a 404 error as shown below:

enter image description here

How can I hit feedbackHandler on form submission?