Facebook Server Sent Event for Live Comments error with status code 404

I'm trying to get comments from Facebook live_videos with Facebook SSE.
Despite I can easily retrieve comments with the {live-video-id}/comments graph api using my test app's page access token, I can't make the SSE to work with the same access token.
Trying to connect with eventsource (code below) keep giving { type: 'error', status: 404, message: 'Not Found' }

async execute() {     this.es = new EventSource(       `https://streaming-graph.facebook.com/${live_video_id}/live_comments?access_token=${page_access_token}`,     );     this.es.onopen = (ev) => {       console.log('onopen', ev);     };     this.es.onmessage = (ev) => {       console.log('onmessage', ev);     };     this.es.onerror = (err) => {       console.error(err);     };   } 

Is there anything else that I'm still missing to get the SSE to work?