Tracklist API - Removed track continues to play

I’m experiencing an issue that I can’t quite understand. I’m clearing my tracklist, then adding songs via the youtube plugin (adding a playlist of music), then triggering the play command. The UI shows my previous track being removed and replaced by the songs in the playlist, and the Now Playing starts the first playlist track, with its album artwork and length. However, the previous track that was supposed to be removed is still playing.

Here’s a video showing what is happening:

Here’s my code: