Real-time queue stats returning empty arrays on CXone v2 Reporting API

Problem
Trying to grab live queue stats from the CXone v2 Reporting API. Docs say it should spit out current wait times and agent counts.
Code

res = requests.get("https://api.nicecxone.com/api/v2/reporting/queues/metrics", headers=headers)
print(res.json())

Error
Hits 200 OK but just returns {"metrics": []}. Swapping the bearer token doesn’t fix it. Probably messing up the time range parameter.
Question
How do I set the interval for real-time pulls? The SDK samples only cover historical buckets anyway. Can’t figure out the live query syntax.