Title is not showing when uploading a video to TikTok via api

I am creating videos on TikTok using their Api. With the video, I also provide a title. The video is showing up in my Inbox for approval as expected, but the title is not showing. Instead I only get a HashTag of the name of the App I am using.

I checked the code a few times and made sure the json structure is correct. What am I missing?

 return await fetch('https://open.tiktokapis.com/v2/post/publish/inbox/video/init/', {
        method: 'POST',
        headers: {
            'Authorization': `Bearer ${accessToken}`,
            'Content-Type': 'application/json; charset=UTF-8'
        },
        body: JSON.stringify({
            post_info: {
                privacy_level: 'PUBLIC_TO_EVERYONE',
                title: "Hello #world",
            },
            source_info: {
                source: 'PULL_FROM_URL',
                video_url: `THE VIDEO URL`
            }
        })
    })