Here's an example response (subscriber name redacted):

  {
    "data": {
      "name": "LASTNAME, FIRSTNAME",
      "line_provider": "Google/Bandwidth.com (SVR)",
      "carrier": "Bandwidth.com",
      "line_type": "landline"
    }
  }

I registered it about 13 years ago. I didn't transfer it from a landline/cell phone, it was picked from a list of Google Voice numbers available in my area code. I've never had Fi.