I am working on a project which is based on micro-service architecture and use the identity server 5.

I set up JWT authentication using the Identity Server 5 as follows:

    public static IServiceCollection AddDefaultAuthentication(this IHostApplicationBuilder builder)
    {
        var services = builder.Services;
        var configuration = builder.Configuration;

        // {
        //   "Identity": {
        //     "Url": "http://identity",
        //     "Audience": "basket"
        //    }
        // }

        var identitySection = configuration.GetSection("Identity");

        if (!identitySection.Exists())
        {
            // No identity section, so no authentication
            return services;
        }

        // prevent from mapping "sub" claim to nameidentifier.
        JsonWebTokenHandler.DefaultInboundClaimTypeMap.Remove("sub");

        services.AddAuthentication().AddJwtBearer(options =>
        {
            var identityUrl = identitySection.GetRequiredValue("Url");
            var audience = identitySection.GetRequiredValue("Audience");
            options.Authority = identityUrl;
            options.RequireHttpsMetadata = false;
        options.Audience = audience;

            options.TokenValidationParameters = new TokenValidationParameters
            {
               
#if DEBUG
                //Needed if using Android Emulator Locally. See https://learn.microsoft.com/en-us/dotnet/maui/data-cloud/local-web-services?view=net-maui-8.0#android
                ValidIssuers = [identityUrl, "https://10.0.2.2:5243"],
#else
                ValidIssuers = [identityUrl],
#endif
                ValidateAudience = false,
                IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Constants.SecurityKey)),
                ValidTypes = new[] { "at+jwt" },
                
            };

        });

        services.AddAuthorization();
        
        return services;
    }

I want to get access token. But my api is not working.

api.MapGet("/token",  async (HttpContext context) => await context.GetTokenAsync("access_token"));

How can I get access token?