Laravel sign in

I can sign up to the database but can't use info from the database to successfully login.

 public function getSignin()
    {
        return view('user.signin');
    }
    public function postSignin(Request $request)
    {
        $this->validate($request, [
            'email' => 'email|required',
            'password' => 'required|min:4'
        ]);
 if (Auth::attempt(['email' => $request->input('email'), 'password' => $request->input('password')])) {
            return redirect()->route('user.profile');
        }
        return redirect()->back();

    }

via Chebli Mohamed