Child Theme Customizer not working

Question

My child theme customizer is not working. I have created a child theme from the parent theme called flash. In the parent theme I can use the customizer just fine and change the layout ect. However, when I activate my child theme nothing in in my customizer working in terms of layout.I feel like the issue lies in my style.css comment. I have researched this and everyone kept saying that it had to do with plugins so I deactivated and activated those one by one and nothing was wrong. So I think it has to do with how I am linking the child theme. I am new to child themes so maybe I'm way off by thinking it has anything to do with the style.css comment, but if someone has any idea why please let me know.

Here is an example of the comment that I had to put in the style.css. I'll include the author of the flash theme's comment in as well.

My child theme style.css comment:

/*
Theme Name: flash-child
Theme URI: https://mywebsite.com/flash-child
Author: me
Author URI: https://mywebsite.com/flash-child
Description: Flash is free responsive multipurpose WordPress theme – truly a 
versatile theme perfect for any type of website you want. Like never before, 
it provides multiple pre-built demos which can be imported in seconds using 
ThemeGrill Demo Importer Plugin. The theme fully integrates with Flash 
Toolkit and SiteOrigin’s Page Builder Plugin that makes theme more user-
friendly and easy. Additionally, theme features multiple blog layouts, 
WooCommerce support, multiple header styles, multiple color options etc.
Version: 1.1.3
License: GNU General Public License v3 or later
License URI: http://www.gnu.org/licenses/gpl-3.0.html
Text Domain: flash
Template: flash
Tags: one-column, two-columns, left-sidebar, right-sidebar, grid-layout, 
custom-background, custom-colors, custom-menu, custom-logo, featured-images, 
footer-widgets, full-width-template, theme-options, threaded-comments, 
translation-ready, blog, e-commerce

Flash is based on Underscores http://underscores.me/, (C) 2012-2016 
Automattic, Inc.
Underscores is distributed under the terms of the GNU GPL v2 or later.

Normalizing styles have been helped along thanks to the fine work of
Nicolas Gallagher and Jonathan Neal http://necolas.github.com/normalize.css/
 */

Flash (parent) theme comment in style.css:

/*
Theme Name: Flash
Theme URI: https://themegrill.com/themes/flash
Author: ThemeGrill
Author URI: https://themegrill.com
Description: Flash is free responsive multipurpose WordPress theme – truly a 
versatile theme perfect for any type of website you want. Like never before, 
it provides multiple pre-built demos which can be imported in seconds using 
ThemeGrill Demo Importer Plugin. The theme fully integrates with Flash 
Toolkit and SiteOrigin’s Page Builder Plugin that makes theme more user-
friendly and easy. Additionally, theme features multiple blog layouts, 
WooCommerce support, multiple header styles, multiple color options etc.
Version: 1.1.3
License: GNU General Public License v3 or later
License URI: http://www.gnu.org/licenses/gpl-3.0.html
Text Domain: flash
Tags: one-column, two-columns, left-sidebar, right-sidebar, grid-layout, 
custom-background, custom-colors, custom-menu, custom-logo, featured-images, 
footer-widgets, full-width-template, theme-options, threaded-comments, 
translation-ready, blog, e-commerce

Flash is based on Underscores http://underscores.me/, (C) 2012-2016 
Automattic, Inc.
Underscores is distributed under the terms of the GNU GPL v2 or later.

Normalizing styles have been helped along thanks to the fine work of
Nicolas Gallagher and Jonathan Neal http://necolas.github.com/normalize.css/
*/

Answer 1

I realize that I did not know that you needed an extra step for the functions.php. Here is the last step I needed.

<?php
function my_theme_enqueue_styles() {

 $parent_style = 'parent-style'; // This is 'twentyfifteen-style' for the 
Twenty Fifteen theme.

    wp_enqueue_style( $parent_style, get_template_directory_uri() . 
'/style.css' );
    wp_enqueue_style( 'child-style',
        get_stylesheet_directory_uri() . '/style.css',
       array( $parent_style ),
       wp_get_theme()->get('Version')
    );
}
add_action( 'wp_enqueue_scripts', 'my_theme_enqueue_styles' );
?>

Answer 2

In addition to the above, make sure to update the version number in your style.css file when updating its content. It seems that customizer caches the CSS and will not update it when it has the old version number (even though the site will work fine).