Getting 401 Unauthorized after moving from .NET Core 2.x to .NET 6

Getting 401 Unauthorized after moving from .NET Core 2.x to .NET 6. Moved the code from the Startup.cs to program.cs.

Application compiles and deploys. I'm able to log in with my credentials, but once it starts making API calls, I get a 401 Unauthorized error.

Any ideas on what I could be missing here?

var logger = NLog.LogManager.Setup().LoadConfigurationFromAppSettings().GetCurrentClassLogger();

try
{
    logger.Debug("init main");

    var builder = WebApplication.CreateBuilder(args);

    ConfigurationManager configuration = builder.Configuration; // allows both to access and to set up the config
    IWebHostEnvironment environment = builder.Environment;

    // Add services to the container.
    builder.Services.AddControllers();
    builder.Services.AddEndpointsApiExplorer();
    builder.Services.AddSwaggerGen();
    builder.Services.AddDistributedMemoryCache();

    //MEW
    builder.Services.Configure<AuthenticationOptions>(configuration.GetSection("Authentication"));
    builder.Services.AddSingleton<GraphApiHelper>();
    builder.Services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
    builder.Services.AddSingleton<IAuthenticationProvider, OnBehalfOfMsGraphAuthenticationProvider>();

    var context = new CustomAssemblyLoadContext();
    var architectureFolder = (IntPtr.Size == 8) ? "64" : "32";
    context.LoadUnmanagedLibrary(Path.Combine(System.IO.Directory.GetCurrentDirectory(), $"lib\\{architectureFolder}\\libwkhtmltox.dll"));

    builder.Services.AddSingleton(typeof(IConverter), new SynchronizedConverter(new PdfTools()));
    builder.Services.AddTransient<INotificationHelper, NotificationHelper>();
    builder.Services.AddTransient<IReportHelper, ReportHelper>();
    builder.Services.AddTransient<TemplateGenerator, TemplateGenerator>();
    builder.Services.AddTransient<IListOfValuesHelper, ListOfValuesHelper>();
    builder.Services.AddTransient<IInventoryService, InventoryService>();

    builder.Services.AddAuthentication(options =>
    {
        options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
        options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
    }).AddJwtBearer(options =>
    {
        var authSettings = configuration.GetSection("MSAuthentication").Get<AuthenticationOptions>();
        options.TokenValidationParameters = new TokenValidationParameters()
        {
            ValidateIssuer = false,
            ValidAudiences = new List<string> { authSettings.Audience, authSettings.Authority }
        };

        options.Authority = authSettings.Authority;
        options.Audience = authSettings.Audience;
        options.TokenValidationParameters.ValidateLifetime = true;
        options.TokenValidationParameters.ClockSkew = TimeSpan.Zero;

        options.SaveToken = true;
    });

    builder.Services.AddAuthorization();

    builder.Services.AddTransient<SubItemService>();
    builder.Services.AddTransient<EstimationHelper>();
    builder.Services.AddTransient<InventoryHelper>();
    builder.Services.AddTransient<UploadCutsHelper>();
    builder.Services.AddTransient<CutsHelper>();
    builder.Services.AddTransient<IStorageService>(provider =>
        new StorageService(configuration.GetValue("AzureStorage:ConnectionString", "")));

    // NLog: Setup NLog for Dependency injection
    builder.Logging.ClearProviders();
    builder.Logging.SetMinimumLevel(Microsoft.Extensions.Logging.LogLevel.Trace);
    builder.Host.UseNLog();

    builder.Services.AddCors(options =>
    {
        options.AddPolicy(name: "_myAllowSpecificOrigins",
            policy =>
            {
                policy.WithOrigins("https://mysite-qa.azurewebsites.net")
                .AllowAnyHeader()
                .AllowAnyMethod();
            });
    });

    var app = builder.Build();

    // Configure the HTTP request pipeline.
    if (app.Environment.IsDevelopment())
    {
        app.UseSwagger();
        app.UseSwaggerUI();
    }

    app.UseHttpsRedirection();

    app.UseRouting();

    app.UseCors("_myAllowSpecificOrigins");

    app.UseAuthorization();

    app.MapControllers();

    app.Run();
}
catch (Exception ex)
{
    //NLog: catch setup errors
    logger.Error(ex, "Stopped program because of exception");
    throw;
}
finally
{
    // Ensure to flush and stop internal timers/threads before application-exit (Avoid segmentation fault on Linux)
    NLog.LogManager.Shutdown();
}

You will need app.UseAuthentication() before app.UseAuthorization()