Log in system error

using AplikacjaWeb.Models;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;

namespace AplikacjaWeb.Pages.Registration
{
    public class RegistrationModel : PageModel
    {
        private readonly UserManager<UserModel> _userManager;
        private readonly SignInManager<UserModel> _signInManager;
        public RegistrationModel(UserManager<UserModel> userManager, SignInManager<UserModel> signInManager)
        {
            _userManager = userManager;
            _signInManager = signInManager;
        }
        [BindProperty]
        public Rejestracja /*Registration in english*/ Input { get; set; }
        public void OnGet()
        {
        }

        public async Task<IActionResult> OnPostAsync()
        {
            if (ModelState.IsValid)
            {
                var user = new UserModel { UserName = Input.Username, Email = Input.Email, PasswordHash = Input.Password };
                var result = await _userManager.CreateAsync(user, Input.Password);
                if (result.Succeeded)
                {
                    await _signInManager.SignInAsync(user, isPersistent: false);
                    return RedirectToPage("/Index");
                }
                else
                {
                    Console.WriteLine("Error");
                }
                foreach (var error in result.Errors)
                {
                    ModelState.AddModelError(string.Empty, error.Description);
                }
            }

            return RedirectToPage("/Index");
        }
    }
}