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

            if (ModelState.IsValid)
            {
                if (!UsersManager.CanSignIn(context, Input.Email))
                {
                    ModelState.AddModelError(string.Empty, "User either not exists or application has not been approved yet");
                    return(Page());
                }

                var result = await signInManager.PasswordSignInAsync(Input.Email, Input.Password, Input.RememberMe, lockoutOnFailure : true);

                if (result.Succeeded)
                {
                    logger.LogInformation("User logged in.");
                    return(LocalRedirect(returnUrl));
                }
                if (result.IsLockedOut)
                {
                    logger.LogWarning("User account locked out.");
                    return(RedirectToPage("./Lockout"));
                }
                else
                {
                    ModelState.AddModelError(string.Empty, "Invalid login attempt.");
                    return(Page());
                }
            }

            return(Page());
        }