<?php
use Microsoft\Graph\GraphServiceClient;
use Microsoft\Graph\Generated\Models\PhoneAuthenticationMethod;
use Microsoft\Graph\Generated\Models\AuthenticationPhoneType;
$graphServiceClient = new GraphServiceClient($tokenRequestContext, $scopes);
$requestBody = new PhoneAuthenticationMethod();
$requestBody->setPhoneNumber('+1 2065555555');
$requestBody->setPhoneType(new AuthenticationPhoneType('mobile'));
$result = $graphServiceClient->users()->byUserId('user-id')->authentication()->phoneMethods()->post($requestBody)->wait();