AAD Authentication between client and .Net Core API - asp.net-core

Question

I m getting this error when I reach the API from the client. I use MSAL, and I can see in the request the token is load.
Here is my startup configuration.
public void ConfigureServices(IServiceCollection services)
{
services.AddControllers();
services.AddAuthentication(defaultScheme: AzureADDefaults.AuthenticationScheme)
.AddAzureAD(options =>
{
options.ClientId = "example";
options.TenantId = "example";
options.ClientSecret = "example";
options.Instance = "https://login.microsoftonline.com/";
});
services.AddCors(options =>
{
options.AddDefaultPolicy(
builder =>
{
builder.WithOrigins("https://localhost:5001", "http://localhost:5000")
.AllowAnyHeader()
.AllowAnyMethod()
.AllowCredentials()
.WithExposedHeaders("Content-Disposition");
});
});
}
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseCors();
//app.UseCors(options =>
//{
// options.WithOrigins("https://localhost:5001", "http://localhost:5000")
// .AllowAnyHeader()
// .AllowAnyMethod()
// .AllowCredentials()
// .WithExposedHeaders("Content-Disposition");
//});
app.UseRouting();
app.UseAuthentication();
app.UseAuthorization();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllers();
});
}

Answer 1

I solve the problem chaingin the Configure Services like this:
services.AddAuthentication(defaultScheme: AzureADDefaults.JwtBearerAuthenticationScheme)
.AddAzureADBearer(options =>
{
options.Instance = Environment.GetEnvironmentVariable("AAD_INSTANCE");
options.TenantId = Environment.GetEnvironmentVariable("AAD_TENANT_ID");
options.ClientId = Environment.GetEnvironmentVariable("AAD_CLIENT_ID");
options.ClientSecret = Environment.GetEnvironmentVariable("AAD_CLIENT_SECRET");
});