fix username double check in create new

src/Controller/AdminController.php

@@ -31,7 +31,6 @@ class AdminController extends AbstractController
         if (!$user) {
             $user = new Users();
             $doctrine->getManager()->persist($user);
-            $user->setUsername($request->request->get('username'));
         }
 
         $user->setName($request->request->get('displayName'));