I have developed an Blazor server app that uses AzureAdB2C to authenticate users. The app is deployed in a kubernetes cluster and is accessible via a subdomain such as myapp.domain.com.

The authentication process works perfectly when there is only one pod running. However, when I increase the number of replicas for the workload, I encounter an HTTP 500 error after the authentication process (from Microsoft redirecting back to my app).

Here is the part of code for the authentication (located in Program.cs) :

builder.Services.AddAuthentication( options =>
    {
        options.DefaultScheme = CookieAuthenticationDefaults.AuthenticationScheme;
        options.DefaultChallengeScheme = OpenIdConnectDefaults.AuthenticationScheme;
    })
    .AddMicrosoftIdentityWebApp(options =>
    {
        configuration.Bind("AzureAd", options);
        options.Events ??= new OpenIdConnectEvents();
        options.Events.OnTokenValidated += OnTokenValidatedFunc;
    })
    ;

async Task OnTokenValidatedFunc(TokenValidatedContext context) {
    // Custom code here
    await Task.CompletedTask.ConfigureAwait(false); }

Could you please assist with this issue?