Analytics Reports API response only returns empty data array

I am following the Downloading Analytics Reports guide which consists of five steps:

1. request the ONGOING report generation for the app once
2. list all analytics report requests for the app
3. list all analytics reports based on the analytics report request id
4. ❌ list all analytics report instances based on the analytics report id
5. list all segments of the analytics report instance to get the download url

I can only complete the third step which returns a list of all available reports.

However when I continue with step four, the request for the analytics report instances returns with a response code 200 but the data array is always empty:

• I am using the Home Screen Widget Installs report but this is also happening for other reports
• Also changing or omitting the filter doesn't change anything

{
   "data": [],
   "links": {
      "self": "https://api.appstoreconnect.apple.com/v1/analyticsReports/{reportId}/instances?filter%5Bgranularity%5D=DAILY"
   },
   "meta": {
      "paging": {
         "total": 0,
         "limit": 50
      }
   }
}

What could be the reason that the data array is empty and how can I fix it because there is no error message?