Windows Validation from Razor Page - asp.net-mvc

Question

I am upgrading an application that works on an intranet, from web forms (framework 4.8) to razor page (net 6). To get a windows user using web form, do the following:
Session("Usuario") = HttpContext.Current.Request.LogonUserIdentity.Name
But I am seeing that in razor page it is not so simple; I have already set windowsAuthentication to true and anonymousAuthentication to false in the launchSetting.json file, and what it shows me is a screen (see image) for the user to enter their authentication credentials, which is not what I require, since that the user has previously validated the domain (by turning on his machine every morning in the company).
Image
I see that with the following instruction the network user is obtained in Razor, and it works, but as long as I validate myself previously on the image screen.
var username = HttpContext.User.Identity.Name;
I have also tried adding the following in Program.cs, but the same always shows that screen.
builder.Services.AddAuthentication(NegotiateDefaults.AuthenticationScheme)
.AddNegotiate();
builder.Services.AddAuthorization(options =>
{
options.FallbackPolicy = options.DefaultPolicy;
});
app.UseAuthentication();
app.UseAuthorization();
Please if you can tell me how to get the windows user without registering again, or in any case indicate if this is the normal way of working in Razor Page.
Thanks.