private async Task SendVerificationEmail(ApplicationUser appUser)
{
string code = await _accountManager.GenerateEmailConfirmationTokenAsync(appUser);
string callbackUrl = EmailTemplates.GetConfirmEmailCallbackUrl(Request, appUser.Id, code);
string message = EmailTemplates.GetConfirmAccountEmail(appUser.UserName, callbackUrl);
await _emailSender.SendEmailAsync(appUser.UserName, appUser.Email, "Confirm your email", message);
}
