Custom Styles CSS

I am trying to use my own custom styles and they aren’t pulling through, I’ve set up my child structure.

My functions file looks like this:

<?php
// Exit if accessed directly
if ( !defined( 'ABSPATH' ) ) exit;

// BEGIN ENQUEUE PARENT ACTION
// AUTO GENERATED - Do not modify or remove comment markers above or below:

if ( !function_exists( 'chld_thm_cfg_locale_css' ) ):
    function chld_thm_cfg_locale_css( $uri ){
        if ( empty( $uri ) && is_rtl() && file_exists( get_template_directory() . '/rtl.css' ) )
            $uri = get_template_directory_uri() . '/rtl.css';
        return $uri;
    }
endif;
add_filter( 'locale_stylesheet_uri', 'chld_thm_cfg_locale_css' );

if ( !function_exists( 'chld_thm_cfg_parent_css' ) ):
    function chld_thm_cfg_parent_css() {
        wp_enqueue_style( 'chld_thm_cfg_parent', trailingslashit( get_template_directory_uri() ) . 'style.css', array( 'airi-onboarding-styles','airi-bootstrap' ) );
    }
endif;
add_action( 'wp_enqueue_scripts', 'chld_thm_cfg_parent_css', 10 );

// END ENQUEUE PARENT ACTION

and my styles look like this:

/*
Theme Name: Airi Child
Theme URI: https://athemes.com/theme/airi
Template: airi
Author: aThemes
Author URI: https://athemes.com
Description: Airi is a powerful, flexible, and modern theme for your business website. Featuring Elementor integration, this theme is an outstanding choice for any kind of company or freelancer site. Bringing a wealth of customization opportunities, Airi is great if you want to start a website from scratch and it's even greater if you want to use a premade Elementor layout from our growing collection. What’s more, the theme offers WooCommerce support, making it easy to sell the products you showcase on your site to your audience.
Tags: custom-background,right-sidebar,custom-colors,custom-logo,custom-menu,featured-images,threaded-comments,translation-ready,full-width-template
Version: 1.0.6.1560031796
Updated: 2019-06-08 22:09:56

*/

h2 {
    font-size: 20px!important;
}

Hello,

Can you please provide a link to your website?

Kind Regards, Roman.
aThemes Support