<?php
use Microsoft\Graph\Beta\GraphServiceClient;
use Microsoft\Graph\Beta\Generated\Models\UnifiedRoleAssignmentMultiple;
$graphServiceClient = new GraphServiceClient($tokenRequestContext, $scopes);
$requestBody = new UnifiedRoleAssignmentMultiple();
$requestBody->setDisplayName('NewName');
$requestBody->setDescription('A new roleAssignment');
$result = $graphServiceClient->roleManagement()->cloudPC()->roleAssignments()->byUnifiedRoleAssignmentMultipleId('unifiedRoleAssignmentMultiple-id')->patch($requestBody)->wait();