How to get access token in Azure

I'm trying to fetch the secrets from the Azure key vault from .Net console application using REST API. Below is the code I'm trying to use for this from net.

Below way I'm trying to get access token and secret value:

 using Newtonsoft.Json; using System;  using System.Net.Http;  using System.Net.Http.Headers;  using System.Text; using System.Text.Json; namespace KeyVaultSecretFetcher { class Program {    static async Task Main(string[] args)    {        // Replace with your Key Vault URL, secret name, and authentication token        string keyVaultUrl = "https://KeyVault.vault.azure.net";        string secretName = "Test3";        //string accessToken = "<your-access-token>";        string tenantId = "tenantId";  // Your tenant ID        string clientId = "clientId";  // Your application (client) ID        string clientSecret = "clientSecret Vaule ";  // Your client secret        string accessToken = await GetAccessToken(tenantId, clientId, clientSecret);        HttpClient client = new HttpClient();        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);        string secretUrl = $"{keyVaultUrl}/secrets/{secretName}?api-version=7.3";        HttpResponseMessage response = await client.GetAsync(secretUrl);        if (response.IsSuccessStatusCode)        {            string responseBody = await response.Content.ReadAsStringAsync();            var secret = System.Text.Json.JsonSerializer.Deserialize<Secret>(responseBody);            Console.WriteLine("Secret value: " + secret.Value);        }        else        {            Console.WriteLine("Error fetching secret: " + response.StatusCode);        }    }    private static async Task<string> GetAccessToken(string tenantId, string clientId, string clientSecret)    {        using (var client = new HttpClient())        {            var body = new StringContent($"grant_type=client_credentials&client_id={clientId}&client_secret={clientSecret}&resource=https://vault.azure.net", Encoding.UTF8, "application/x-www-form-urlencoded");            var response = await client.PostAsync($"https://login.microsoftonline.com/{tenantId}/oauth2/token", body);            response.EnsureSuccessStatusCode();            var jsonResponse = await response.Content.ReadAsStringAsync();            dynamic tokenResponse = JsonConvert.DeserializeObject(jsonResponse);            return tokenResponse.access_token;        }    }    class Secret    {        public string Value { get; set; }    }  } }

However, I'm unable to fetch the secret value. Is there anything wrong in the code or settings?

Notes

This is how API permission is given:

and, app permission is disabled somehow (not sure why). So I have given delegated permission as below:

How to get the secret value? I need to achieve this via REST API only.