ASP.Net Core 3.1 Aplication lost session vars after deploy - asp.net-core

Question

There is a problem, the application uses the session, when launched on the local machine, the session lasts a long time. But when we deploy the server, session data disappears with inconsistent regularity. Sometimes it may take half an hour, sometimes already at the second transition, the application considers that there is no variable in the session. What could be the problem?
Startup.cs
public void ConfigureServices(IServiceCollection services)
{
services.AddDistributedMemoryCache();
services.AddSession();
services.AddControllersWithViews().AddJsonOptions(options =>
{
options.JsonSerializerOptions.Encoder = JavaScriptEncoder.Create(UnicodeRanges.All);
});
services.Configure<WebEncoderOptions>(options =>
{
options.TextEncoderSettings = new TextEncoderSettings(UnicodeRanges.All);
});
services.AddMemoryCache();
services.AddHttpClient();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
System.Diagnostics.Debug.WriteLine("This is development env");
app.UseDeveloperExceptionPage();
// HACK
// Set worker threads as HElios sets them too low for IIS Express
// https://github.com/aspnet/Home/issues/94
int newLimits = 100 * Environment.ProcessorCount; // this is actually # cores (including hyperthreaded cores)
int existingMaxWorkerThreads;
int existingMaxIocpThreads;
System.Threading.ThreadPool.GetMaxThreads(out existingMaxWorkerThreads, out existingMaxIocpThreads);
System.Threading.ThreadPool.SetMaxThreads(Math.Max(newLimits, existingMaxWorkerThreads), Math.Max(newLimits, existingMaxIocpThreads));
}
else
{
app.UseExceptionHandler("/Home/Error");
// The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
app.UseHsts();
}
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseRouting();
app.UseAuthorization();
app.UseSession();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllerRoute(
name: "default",
pattern: "{controller=Home}/{action=Index}/{id?}");
});
}
Set up session var
[HttpPost]
public async Task<JsonResult> UserCheck(string surname)
{
Boolean status = false;
String error_msg = "Что то пошло не так";
try
{
Guid? UserId = null;
if (String.IsNullOrWhiteSpace(surname))
{
error_msg = "Не указана фамилия";
}
else
{
UserId = await apm.GetUser(surname);
if (UserId != null && UserId != Guid.Empty)
{
HttpContext.Session.SetString("UserId", UserId.ToString());
status = true;
error_msg = "";
}
}
return Json(new { status, error_msg, guid = UserId });
}
catch (Exception e)
{
return Json(new { status, error_msg });
}
}
Get session vars
public IActionResult Test()
{
string strUserId = HttpContext.Session.GetString("UserId");
if (String.IsNullOrWhiteSpace(strUserId))
{
return RedirectToAction("Index", "Home");
}
else
{
return View();
}
}