Can't get Oauth to work... please help

Here's my complete code.. and I tried and it doesn't work

namespace LittlePageUpload3
{
    using Dropbox.Api;
    using System;
    using System.Diagnostics; // For Process.Start
    using System.Runtime.InteropServices;
    using System.Threading.Tasks;

    public partial class Program
    {
        static async Task Main(string[] args)
        {
            const string AppKey = "xtva8nnzc76bn1g"; // Replace with your App Key
            const string AppSecret = "XXXX"; // Replace with your App Secret
            const string RedirectUri = "http://localhost:8080/"; // Replace with your Redirect URI

            // Generate a unique state for security
            string oauth2State = Guid.NewGuid().ToString("N");

            // Get the authorization URI
            Uri authorizeUri = DropboxOAuth2Helper.GetAuthorizeUri(
                OAuthResponseType.Code, 
                clientId: AppKey,
                new Uri(RedirectUri),
                state: oauth2State,
                tokenAccessType: TokenAccessType.Offline 
                
            );

            // Open the URI in the user's default browser
            Console.WriteLine("Opening Dropbox authorization in your browser...");

            
            Console.WriteLine("authorizeUri: " + authorizeUri.ToString());
            Process.Start(new ProcessStartInfo("cmd", $"/c start {authorizeUri}") { CreateNoWindow = true });
            

            Console.WriteLine("Please authorize the app in your browser and copy the code from the redirect URL.");
            Console.Write("Enter the authorization code: ");
            string code = Console.ReadLine();

            // Exchange the authorization code for access and refresh tokens
            var tokenResult = await DropboxOAuth2Helper.ProcessCodeFlowAsync(
                code: code,
                appKey: AppKey,
                appSecret: AppSecret,
                redirectUri: RedirectUri
            );

            // Store tokenResult.AccessToken and tokenResult.RefreshToken securely
            Console.WriteLine($"Access Token: {tokenResult.AccessToken}");
            Console.WriteLine($"Refresh Token: {tokenResult.RefreshToken}");

        }
    }
}

My control panel looks like this: