Laravel + JWT Authentication not working on my side - angularjs

Question

am following up This tutorial to learn the jwt cool stuff. but when am testing the first bit of the server API with POSTMAN only the id,password fields are the one being inserted in the database. When I try to login with POSTMAN I get
MethodNotAllowedHttpException in RouteCollection.php line 218: from the server preview
my routes
Route::post('api/register', 'TokenAuthController#register');
Route::post('api/authenticate', 'TokenAuthController#authenticate');
Route::get('api/authenticate/user', 'TokenAuthController#getAuthenticatedUser');
my controller
<?php
namespace App\Http\Controllers;
use App\Http\Controllers\Controller;
use Tymon\JWTAuth\Facades\JWTAuth;
use Tymon\JWTAuth\Exceptions\JWTException;
use App\Http\Requests;
use Illuminate\Http\Request;
use App\User;
use Illuminate\Support\Facades\Hash;
class TokenAuthController extends Controller
{
public function authenticate(Request $request)
{
$credentials = $request->only('email', 'password');
try {
if (!$token = JWTAuth::attempt($credentials)) {
return response()->json(['error' => 'invalid_credentials'], 401);
}
} catch (JWTException $e) {
return response()->json(['error' => 'could_not_create_token'], 500);
}
// if no errors are encountered we can return a JWT
return response()->json(compact('token'));
}
public function getAuthenticatedUser()
{
try {
if (!$user = JWTAuth::parseToken()->authenticate()) {
return response()->json(['user_not_found'], 404);
}
} catch (Tymon\JWTAuth\Exceptions\TokenExpiredException $e) {
return response()->json(['token_expired'], $e->getStatusCode());
} catch (Tymon\JWTAuth\Exceptions\TokenInvalidException $e) {
return response()->json(['token_invalid'], $e->getStatusCode());
} catch (Tymon\JWTAuth\Exceptions\JWTException $e) {
return response()->json(['token_absent'], $e->getStatusCode());
}
return response()->json(compact('user'));
}
public function register(Request $request)
{
$newuser = $request->all();
$password = Hash::make($request->input('password'));
$newuser['password'] = $password;
return User::create($newuser);
}
}
I don't know where am messing out this code.