I am trying to configure Azure AD B2C authentication with my Web API and although it builds and compiles fine, after passing in a token with a request, it logs:

 ... has a valid signature.
Lifetime of the token is valid.
Audience validated.
Creating claims from the validated token

But in the controller, the value of User.IsAuthenticated is false.

This is the controller:

using Microsoft.AspNetCore.Mvc;
using SoundShowdownAPI.Models;

namespace SoundShowdownAPI.Controllers
{
    [ApiController]
    [Route("[controller]")]
    public class UsersController : ControllerBase
    {
        private readonly ILogger<UsersController> _logger;

        public UsersController(ILogger<UsersController> logger)
        {
            _logger = logger;
        }

        [Route("me")]
        [HttpGet]
        public User Me()
        {
            var user = new User();
            user.Name = this.User.Identity.Name;
            user.Email = "unimplemented";
            return user;
        }
    }
}

This is the program.cs file:

using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.Identity.Web;
using Microsoft.IdentityModel.Logging;
using System.Security.Principal;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

// Set up authentication via Microsoft Identity

builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
    .AddMicrosoftIdentityWebApi(options =>
    {
        builder.Configuration.Bind("AzureAdB2C", options);
        options.TokenValidationParameters.NameClaimType = "name";
    },
    options =>
    {
        builder.Configuration.Bind("AzureAdB2C", options);
    });


builder.Services.AddControllers();

builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

var app = builder.Build();

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

app.UseHttpsRedirection();

app.UseAuthentication();
app.UseAuthorization();

app.MapControllers();

IdentityModelEventSource.ShowPII = true;
IdentityModelEventSource.LogCompleteSecurityArtifact = true;

app.Run();

This is the appsettings.json file:

{
    "Logging": {
        "LogLevel": {
             "Default": "Information",
             "Microsoft.AspNetCore": "Warning"
        }
    },
    "AllowedHosts": "*",

    "AzureAdB2C": {
        "Instance": "https://jfgamesinc.b2clogin.com/",
        "Domain": "jfgamesinc.onmicrosoft.com",
        "ClientId": "989ba9ff-890c-41e7-b8e9-3a3b63f575fb",
        "SignUpSignInPolicyId": "B2C_1_SignUpIn"
    }
}