NuSOAP webservice insert data mysql

I want to use the NuSOAP webservice to insert data on my mysql database.

I have this example below that shows how to "print" data from the database. But I want to insert...

server.php

<?php 

require_once "lib/nusoap.php";

$server = new soap_server();
$server->configureWSDL("mi primer ws","urn:mundopccmb");

if(!isset($HTTP_RAW_POST_DATA)){
    $HTTP_RAW_POST_DATA = file_get_contents("php://input");
}


function cargarVehiculos($id){
    $cn = mysqli_connect("localhost","root","","db_transporte");
    $vehiculos = $cn->query("SELECT Codigo,flota,p_neto FROM vehiculos WHERE Codigo=".$id);
    $ArrVehiculos = [];
    while ($vehiculo = mysqli_fetch_array($vehiculos,MYSQLI_ASSOC)) {
        $ArrVehiculos[] = $vehiculo ;
    }
    return json_encode($ArrVehiculos);
}

$server->register("cargarVehiculos",array("id"=>"xsd:int"),
                                    array("return"=>"xsd:string"),
                                    "urn:mundopccmb",
                                    "urn:mundopccmb#cargarVehiculos",
                                    "rpc",
                                    "encoded",
                                    "Carga todos los vehículos"
                  );

$server->service($HTTP_RAW_POST_DATA);

client.php

<?php 

require_once "lib/nusoap.php";


$client = new nusoap_client("http://www.webservice.fya/index.php?wsdl");
$vehiculos = $client->call("cargarVehiculos",array("id"=>10));
$vehiculos = json_decode($vehiculos);

echo "<ul>";
foreach ($vehiculos as $vehiculo) {
    echo "<li>".$vehiculo->Codigo." ".$vehiculo->flota." ".$vehiculo->p_neto." "."</li>";
}
echo "</ul>";