Custom form action problem when error thrown

[ghost]

I've written a custom form action which at the moment, simply queries a URL and hopefully returns some json. I was just testing the function with an invalid URL ( using wp_remote_get() ), and I expect a message in red to appear on the webpage under the form.

Looks like it's working fine when editing the page in Elementor.

However, with a live page - it doesn't show the form error at all and throws a console error instead.

Anyone know how to fix this? I can post more code if requested.

Here is the Run function.

  class Custom_Actionextends \ElementorPro\Modules\Forms\Classes\Action_Base {

  public function run( $record, $ajax_handler ) {

    $settings = $record->get( 'form_settings' );
    if ( empty( $settings['productName'] ) ) {
       return;
    }
    
    $raw_fields = $record->get( 'fields' );
    
    $fields = [];
    foreach ( $raw_fields as $id => $field ) {
        $fields[ $id ] = $field['value'];
    }
    
    $toEmail = $fields['email'];
    
    $response = wp_remote_get( 'url/to/get/json' );
    
    $response_code = wp_remote_retrieve_response_code( $response );
    $response_message = wp_remote_retrieve_response_message( $response );

    if ( empty($response_code) ) {
        $response_code = 500;
        $response_message = "Internal server error.";
    }
    
    if ( Is_wp_error( $response ) || $response_code != 200 ) {
        $ajax_handler->add_error_message( "An error occurred attempting to send the form: ".$error_message );
        $ajax_handler->is_sucess = false;
        return;
    }
    
    $body = wp_remote_retrieve_body( $response );
    
    $data = json_decode( $body );
    
    $ajax_handler->add_response_data( true, $data, $response_code );
  }
}

 add_action( 'elementor_pro/init', function() {

  $custom_action= new Custom_Action();

  \ElementorPro\Plugin::instance()->modules_manager->get_modules( 'forms' )->add_form_action( $custom_action->get_name(), $custom_action);
  } );