ADA authentication permission error with multiple tenants

I am new to Azure AD Authentication. I created the application in blue and made it layered and set its permissions as follows

• Login and read user profile

• Reading directory data

Here is my code Startup.Auth.cs

public partial class Startup
    {
        private static string clientId = ConfigurationManager.AppSettings["ida:ClientId"];
        private string appKey = ConfigurationManager.AppSettings["ida:ClientSecret"];
        private string graphResourceID = "https://graph.windows.net";
        private static string aadInstance = ConfigurationManager.AppSettings["ida:AADInstance"];
        private string authority = aadInstance + "common";
        private ApplicationDbContext db = new ApplicationDbContext();

        public void ConfigureAuth(IAppBuilder app)
        {

            app.SetDefaultSignInAsAuthenticationType(CookieAuthenticationDefaults.AuthenticationType);

            app.UseCookieAuthentication(new CookieAuthenticationOptions { });

            app.UseOpenIdConnectAuthentication(
                new OpenIdConnectAuthenticationOptions
                {
                    ClientId = clientId,
                    Authority = authority,
                    TokenValidationParameters = new System.IdentityModel.Tokens.TokenValidationParameters
                    {
                        // instead of using the default validation (validating against a single issuer value, as we do in line of business apps), 
                        // we inject our own multitenant validation logic
                        ValidateIssuer = false,
                    },
                    Notifications = new OpenIdConnectAuthenticationNotifications()
                    {
                        SecurityTokenValidated = (context) => 
                        {
                            return Task.FromResult(0);
                        },
                        AuthorizationCodeReceived = (context) =>
                        {
                            var code = context.Code;

                            ClientCredential credential = new ClientCredential(clientId, appKey);
                            string tenantID = context.AuthenticationTicket.Identity.FindFirst("http://schemas.microsoft.com/identity/claims/tenantid").Value;
                            string signedInUserID = context.AuthenticationTicket.Identity.FindFirst(ClaimTypes.NameIdentifier).Value;

                            AuthenticationContext authContext = new AuthenticationContext(aadInstance + tenantID, new ADALTokenCache(signedInUserID));
                            AuthenticationResult result = authContext.AcquireTokenByAuthorizationCode(
                                code, new Uri(HttpContext.Current.Request.Url.GetLeftPart(UriPartial.Path)), credential, graphResourceID);

                            return Task.FromResult(0);
                        },
                        AuthenticationFailed = (context) =>
                        {
                            context.OwinContext.Response.Redirect("/Home/Error");
                            context.HandleResponse(); // Suppress the exception
                            return Task.FromResult(0);
                        }
                    }
                });

        }
    }

      

        
        
        
      

    

But when I try to run the app and login it gives me the error

    You can't access this application 
    XXXXXXX needs permission to access resources in your organization that only an admin can grant. 
    Please ask an admin to grant permission to this app before you can use it.

    Have an admin account? Sign in with that account 
    Return to the application without granting consent