There was a problem when working with Spotify API, trying to get the value of the key of the duration of the track being played, but as a result “undefined”. I get it like this:

const data = await spotifyApi.getMyCurrentPlaybackState(userID);

console.log(data.body.duration_ms);

If you try to output Body yourself, then it has this key in it, and it has the value of the length of the track in milliseconds

console.log(data.body)