public async Task <IActionResult> OnPostAsync(string returnUrl = null)
        {
            returnUrl = returnUrl ?? Url.Content("~/");

            if (ModelState.IsValid)
            {
                // This doesn't count login failures towards account lockout
                // To enable password failures to trigger account lockout, set lockoutOnFailure: true
                var userName = Input.Email;
                if (IsValidEmail(Input.Email))
                {
                    var userCheck = await _userManager.FindByEmailAsync(Input.Email);

                    if (userCheck != null)
                    {
                        userName = userCheck.UserName;
                    }
                }
                var user = await _userManager.FindByNameAsync(userName);

                if (user != null)
                {
                    if (!user.IsActive)
                    {
                        return(RedirectToPage("./Deactivated"));
                    }
                    else if (!user.EmailConfirmed)
                    {
                        Notify.AddErrorToastMessage("Email Not Confirmed.");
                        ModelState.AddModelError(string.Empty, "Email Not Confirmed.");
                        return(Page());
                    }
                    else
                    {
                        var result = await _signInManager.PasswordSignInAsync(userName, Input.Password, Input.RememberMe, lockoutOnFailure : false);

                        if (result.Succeeded)
                        {
                            _logger.LogInformation("User logged in.");
                            Notify.AddSuccessToastMessage($"Logged in as {userName}.");
                            return(LocalRedirect(returnUrl));
                        }
                        if (result.RequiresTwoFactor)
                        {
                            return(RedirectToPage("./LoginWith2fa", new { ReturnUrl = returnUrl, RememberMe = Input.RememberMe }));
                        }
                        if (result.IsLockedOut)
                        {
                            Notify.AddWarningToastMessage("User account locked out.");
                            _logger.LogWarning("User account locked out.");
                            return(RedirectToPage("./Lockout"));
                        }
                        else
                        {
                            Notify.AddErrorToastMessage("Invalid login attempt.");
                            ModelState.AddModelError(string.Empty, "Invalid login attempt.");
                            return(Page());
                        }
                    }
                }
                else
                {
                    Notify.AddErrorToastMessage("Email / Username Not Found.");
                    ModelState.AddModelError(string.Empty, "Email / Username Not Found.");
                }
            }

            // If we got this far, something failed, redisplay form
            return(Page());
        }