Ajax with hook_form_alter

Question

I have develop many custom form and added ajax functionality with the form field, Ajax code works like a charm with my custom form.

But now i have a situation where i have add ajax callback to the title field of node.

For this i am using hook_form_alter, and adding same ajax code to title, but ajax event is not firing up for title field.

below is my code:

function module_form_FORM_ID_alter(&$form, FormStateInterface $form_state, $form_id){

  $form['title']['#ajax'] = [
    'callback' => 'module_updateCategoryDropDown',
    'event' => 'change',
    'progress' => [
      'type' => 'throbber',
      'message' => t('Verifying...'),
     ],
 ];
}

function module_updateCategoryDropDown(array &$form, FormStateInterface $form_state){
  /* form category dropdown code is here */
}