Alter messages for incomplete address in shipping caluculator

functions.php

add_filter( 'woocommerce_cart_no_shipping_available_html', 'wf_custom_message_for_incomplete_address', 10, 1 ); // Alters message on Cart page
add_filter( 'woocommerce_no_shipping_available_html', 'wf_custom_message_for_incomplete_address', 10, 1 ); // Alters message on Checkout page
function wf_custom_message_for_incomplete_address( $default ) {
	
	$wf_cart_country	= WC()->customer->get_shipping_country();
	$wf_cart_state 		= WC()->customer->get_shipping_state();
	$wf_cart_postcode 	= WC()->customer->get_shipping_postcode();
	
	$shipping_msg_array = array();
	
	empty($wf_cart_country) ? $shipping_msg_array[] = 'Country' : '';
	empty($wf_cart_state) ? $shipping_msg_array[] = 'State' : '';
	empty($wf_cart_postcode) ? $shipping_msg_array[] = 'Postcode' : '';
 
    if( !empty( $shipping_msg_array ) ){
		if( count($shipping_msg_array) > 1 ){
			$shipping_msg = implode(", ", $shipping_msg_array);
			return $shipping_msg . " are empty.Please fill up those fields";
		}else{
			$shipping_msg = $shipping_msg_array[0];
			return $shipping_msg . " is empty.Please fill up the field";
		}
	}
	else
       return $default;
}