Call a secure webapi from okta-aspnet-webforms-example.sln

I’m running okta-aspnet-webforms-example.sln

I add a button.

I have a .net (core) 6.0 webapi, that is secured by okta. Its’ named SpnApi.

How can I call a method on SpnApi that has [Authorize]'d via Okta from that button.

I’m able to call one with [AllowAnonymous],

protected void Button1_Click( object sender, EventArgs e )
                string buffer = string.Empty;
                // Create an HttpClient instance 
                HttpClient client = new HttpClient();

                var result = AsyncHelper.RunSync<string>( () => client.GetStringAsync( "http://localhost:44331/DoCdssLoginTestsAllowAnonymous?sAdName=bob.bob" ) );
                TextBox1.Text = result;

            catch ( Exception ex )


but the other, I get (as expected) a 401, since no token is included. how do i modify the code above to call the secured api method?