Add Custom Checkout Field Woocommerce

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// Add custom checkout field
add_action('woocommerce_after_order_notes', 'howd_you_find_us_bro');

function howd_you_find_us_bro($checkout) {

    echo '<div id="hdfoamb"><h3>' . __('How did you find my business?') . '</h3>';

    woocommerce_form_field( 'customer_acquisition', array(
        'type'          => 'textarea',
        'class'         => array('my-field-class form-row-wide'),
        'label'         => __(''),
        'placeholder'   => __('Please let us know how you found our business.'),
        ), $checkout->get_value( 'customer_acquisition' ));

    echo '</div>';

}

// Save custom checkout field
add_action('woocommerce_checkout_update_order_meta', 'howd_you_find_us_bro_update_order_meta');

function howd_you_find_us_bro_update_order_meta($order_id) {
    if ($_POST['customer_acquisition']) {
        update_post_meta($order_id, 'Customer Acquisition', esc_attr($_POST['customer_acquisition']));
    }
}