Error: The required information to complete authentication was not provided

Symptom:

    When we run  "oci os ns get"  in Oracle Cloud, we get below error:
WARNING: Your computer time: 2020-03-19T08:21:13.667808+00:00 differs from the server time: 2020-03-19T08:27:28+00:00 by more than 5 minutes. This can cause authentication errors connecting to services.
ServiceError:
{
    "code": "NotAuthenticated",
    "message": "The required information to complete authentication was not provided.",
    "opc-request-id": "iad-1:LadKpOv52VZyJpLcapW1oD_MfXrxSEpICkJh90iR5Xke2k437wa7PQUaP99kuGSQ",
    "status": 401
}

Solution:

   We often ignore the warning message. The box OS we run oci is indeed had more than 5 minutes time differences with the server.

   Sync the local time and fix the issue