401 error (no message)

request

curl --request GET \
     --url 'https://dialpad.com/api/v2/users?state=active&limit=10' \
     --header 'accept: application/json' \
     --header 'authorization: Bearer ????????????????????????????????????????????????????????????????????????????????????????????DCrF6WJa'

response

{
    "error": {
        "code": 401,
        "errors": [
            {
                "domain": "global",
                "message": "",
                "reason": "required"
            }
        ],
        "message": ""
    }
}

I don't know why I got a 401 error.

Office Name: 株式会社オロ
OAuth App Name: dexeco (I emailed to change the name from dexeco to dxeco.)