I am trying to pull users presence data in C#

I was able to get the AccountId and the ExtensionId from here:

Here is my code:

using System;

using System.Threading.Tasks;

using RingCentral;



namespace Send_SMS

{

    class Program

    {

        const string RINGCENTRAL_CLIENTID = "<>";

        const string RINGCENTRAL_CLIENTSECRET = "<>";



        const string RINGCENTRAL_USERNAME = "<>";

        const string RINGCENTRAL_PASSWORD = "<>";

        const string RINGCENTRAL_EXTENSION = "<>";



        const string RINGCENTRAL_PRESENCE_USER = "<>";

        const string RINGCENTRAL_PRESENCE_EXT = "101";





        static RestClient restClient;



        static void Main(string[] args)

        {



            restClient = new RestClient(RINGCENTRAL_CLIENTID, RINGCENTRAL_CLIENTSECRET, false);

            restClient.Authorize(RINGCENTRAL_USERNAME, RINGCENTRAL_EXTENSION, RINGCENTRAL_PASSWORD).Wait();

            get_presence().Wait();



        }

 

        static private async Task get_presence()

        {



            // OPTIONAL QUERY PARAMETERS

            ReadUserPresenceStatusParameters readUserPresenceStatusParameters = new ReadUserPresenceStatusParameters

            {

                //detailedTelephonyState = true,

                //sipData = true

            };



            var response = await restClient.Restapi().Account(RINGCENTRAL_PRESENCE_USER).Extension(RINGCENTRAL_PRESENCE_EXT).Presence().Get(readUserPresenceStatusParameters);



            Console.WriteLine("Presence for Test Account: " + response.presenceStatus);

        }



    }

}

Everything in <> is filled out of course, and tested with the SMS_Send tutorial.

My error:

Content: {"errorCode":"CMN-102","message":"Resource for parameter [extensionId] is not found","errors":[{"errorCode":"CMN-102","message":"Resource for parameter [extensionId] is not found","parameterName":"extensionId"}],"parameterName":"extensionId"}

Thanks in advance. I'm really struggling to understand the account/extension side of this API.