<?php
use Microsoft\Graph\GraphServiceClient;
use Microsoft\Graph\Generated\Users\Item\OnlineMeetings\Item\Transcripts\Item\Content\ContentRequestBuilderGetRequestConfiguration;
$graphServiceClient = new GraphServiceClient($tokenRequestContext, $scopes);
$requestConfiguration = new ContentRequestBuilderGetRequestConfiguration();
$queryParameters = ContentRequestBuilderGetRequestConfiguration::createQueryParameters();
$queryParameters->format = "text/vtt";
$requestConfiguration->queryParameters = $queryParameters;
$graphServiceClient->users()->byUserId('user-id')->onlineMeetings()->byOnlineMeetingId('onlineMeeting-id')->transcripts()->byCallTranscriptId('callTranscript-id')->content()->get($requestConfiguration)->wait();