Api call through VS studio Console in c# fails

Question

HI, the Api call (Patch) through Visual Studio Console app is failing with the following error "The remote server returned an error: (403) Forbidden.". The same call works fine when I use Postman(Basic authentication with username and password). I get the response back from Postman. What could be the issue with the c# program. Please suggest. Thanks in advance. .NET framework 4.7.

using System;
using System.Data;
using System.Data.SqlClient;
using System.IO;
using System.Linq;
using System.Net;
using System.Globalization;
using System.Text.RegularExpressions;
using System.Xml;
using System.Web;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            var result = string.Empty;
            string json = @"{
""schemas"": [
        ""urn:scim:schemas:core:2.0:User"",
        ""urn:scim:schemas:extension:fa:2.0:faUser""
    ],
    ""userName"": ""ZMatt.Dandon @cmpy.com"",
    ""name"": {
        ""familyName"": ""Dandon"",
        ""givenName"": ""ZMatt""
    },
    ""displayName"": ""ZMatt Dandon"",
    ""preferredLanguage"": ""en"",
    ""active"": false
}";
            string url = @"https://url/hcmRestApi/scim/Users/C8FF94E381891376E050480A69294891";
            ServicePointManager.Expect100Continue = true;
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;

            // Making Web Request
            HttpWebRequest Req = (HttpWebRequest)WebRequest.Create(url);
            Req.Credentials = new NetworkCredential("UserName", "Password");

            //Content_type    
            Req.ContentType = "application/vnd.oracle.adf.action+json";

            //HTTP method    
            Req.Method = "PATCH";

            using (var streamWriter = new StreamWriter(Req.GetRequestStream()))
            {
                streamWriter.Write(json);
            }

            var httpResponse = (HttpWebResponse)Req.GetResponse();
            using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
            {
                result = streamReader.ReadToEnd();
            }


        }
    }
}

Answer 1

Basic authentication is base64 encoded and added to the HTTP Authorization header. See this SO post.

Answer 2

Are "UserName" and "Password" your real credentials?

Answer 3

OK, @AgaveJoe that is correct. THank you so much for the answer.

Here is the updated code

  // Making Web Request  
    HttpWebRequest Req = (HttpWebRequest)WebRequest.Create(url);  
    //Req.Credentials = new NetworkCredential("00OracleERPuser", "PMT12345");  
    string encoded = System.Convert.ToBase64String(Encoding.GetEncoding("UTF-8")  
                       .GetBytes("UserName" + ":" + "Password"));  
    Req.Headers.Add("Authorization", "Basic " + encoded);