Get CPU Metrics From API

Why do I get an empty result when making request to get CPU Metrics?

both using HTTP request and pydo package gives me an empty result.

example request from docs:

curl -X 'GET' \
  'https://api.digitalocean.com/v2/monitoring/metrics/droplet/cpu?host_id=3400xxxxx&start=1620683817&end=1620705417' \
  -H 'accept: application/json' \
  -H 'Authorization: Bearer dop_v1_3xaxxfxxx'

The result:

{
  "status": "success",
  "data": {
    "resultType": "matrix",
    "result": []
  }
}

I was also trying the Swagger from the docs but doesn’t work either. The access in API settings is full access, but still get an empty result.

What do I miss?