Heroku Platform API's users endpoint - How to get the last login date of team members

General
1

I want to retrieve the last login date of team members using the Platform API. I can successfully get the last login date of the sole administrator who created the team, but I am unable to retrieve it for other team members. Why is this the case?

Error response:

{
  "resource": "user",
  "id": "not_found",
  "message": "Couldn't find that user."
}

Endpoint for retrieving team members: https://devcenter.heroku.com/ja/articles/platform-api-reference#-67

Scope: global

Command I tried:

curl -n https://api.heroku.com/users/<uuid> \
-H "Accept: application/vnd.heroku+json; version=3" \
-H "Authorization: Bearer HRKU-<Access Token>"

uuid I tried: user:id, id