Notification API WebSocket: conversation/updated subscription returns 4004

NICE CXone API & Integrations
1

Trying to subscribe to conversation/updated events via the Notification API WebSocket using the JS SDK. Getting a 4004 error code in the subscription response payload: {"code": 4004, "message": "Invalid topic"}. Confirmed the token has notification:subscribe scope and the topic string matches the docs exactly. Here’s the snippet:

const ws = new WebSocket('wss://api.mypurecloud.com/api/v2/analytics/events');
ws.on('open', () => {
 ws.send(JSON.stringify({
 action: 'subscribe',
 topics: ['conversation/updated']
 }));
});

Any idea why this is failing?