Asp.NET identity signin method returns invalid login all the time

I have integrated asp.net identity into my mvc application I have created a custom class for signup records to asp.netuser table it works fine signup, but on sign in with below line i am getting error 

 var result = await SignInManager.PasswordSignInAsync(model.Email, model.Password, model.RememberMe, shouldLockout: false);

     default:
                    ModelState.AddModelError("", "Invalid login attempt.");
                    return View(model);

this is return all the time even though my email and password are right