Set custom thumbnail via YoutubeAPI doesn't work. Can someone tell me why?
<p>I try to upload custom thumbnail for video.</p>

<p>Official documentation link: <a href="https://developers.google.com/youtube/v3/docs/thumbnails/set" rel="noreferrer">https://developers.google.com/youtube/v3/docs/thumbnails/set</a></p>

<p>Used scopes for requested access token was:<br>
https*://www.googleapis.com/auth/youtube.force-ssl<br>
https*://www.googleapis.com/auth/youtubepartner<br>
https*://www.googleapis.com/auth/userinfo.profile<br>
https*://www.googleapis.com/auth/userinfo.email<br>
https*://www.googleapis.com/auth/youtube<br>
https*://www.googleapis.com/auth/youtube.upload<br></p>

<p>Then i get response:</p>

<p>Error calling PUT <a href="https://www.googleapis.com/upload/youtube/v3/thumbnails/set?videoId=my_video_id&amp;uploadType=resumable&amp;upload_id=my_upload_id" rel="noreferrer">https://www.googleapis.com/upload/youtube/v3/thumbnails/set?videoId=my_video_id&amp;uploadType=resumable&amp;upload_id=my_upload_id</a>: (403) The authenticated user doesnt have permissions to upload and set custom video thumbnails.</p>

<p>I set all needed scopes and still have not permissions. How can i resolve it?
Thanks.</p>