chechout.php

// Billing fields woocommerce checkout
add_filter( 'woocommerce_checkout_fields' , 'custom_override_checkout_fields' );
function custom_override_checkout_fields( $fields ) {
    unset($fields['billing']['billing_company']);
    unset($fields['billing']['billing_address_2']);
    unset($fields['billing']['billing_country']);
    unset($fields['billing']['billing_state']);

    // Setting placeholder texts
    $fields['billing']['billing_first_name']['required'] = true;
    $fields['billing']['billing_first_name']['placeholder'] = "Förnamn";

    $fields['billing']['billing_last_name']['required'] = true;
    $fields['billing']['billing_last_name']['placeholder'] = "Efternamn";

    $fields['billing']['billing_address_1']['required'] = true;
    $fields['billing']['billing_address_1']['placeholder'] = "Adress";

    $fields['billing']['billing_city']['required'] = true;
    $fields['billing']['billing_city']['placeholder'] = "Stad";

    $fields['billing']['billing_postcode']['required'] = true;
    $fields['billing']['billing_postcode']['placeholder'] = "Postnummer";

    $fields['billing']['billing_phone']['required'] = true;
    $fields['billing']['billing_phone']['placeholder'] = "Telefon";

    $fields['billing']['billing_email']['placeholder'] = "E-post";
	$fields['billing']['billing_email']['required'] = true;

// Comments are required
	$fields['order']['order_comments']['required'] = true;

    return $fields;
}

// Hide order comments if no coupon is used
add_action( 'woocommerce_before_checkout_form' , 'product_checkout_custom_content' );

function product_checkout_custom_content() {
    global $woocommerce;

	$msgs = array('mycouponcode'=>'');

	$applied_coupon = $woocommerce->cart->applied_coupons;
		if( ! array_key_exists($applied_coupon[0], $msgs) ) {

// Hide order comments
		unset( $fields['order']['order_comments'] );
		add_filter( 'woocommerce_enable_order_notes_field', '__return_false' );
$fields['order']['order_comments']['required'] = false;
return $fields;
// 			echo $msgs[$applied_coupon[0]];
		}
}