Почему ошибка Bad Request, status=400 при загрузке картинок?

Использую sprin boot Ошибка Whitelabel Error Page This application has no explicit mapping for /error, so you are seeing this as a fallback. Tue Jan 25 13:54:17 YEKT 2022 There was an unexpected error (type=Bad Request, status=400). Controller

@GetMapping("/uploadtest")
    public String uploadtest(Model model) {
         return "upload";
    }

    @PostMapping("/postupload")
    public String postupload(@RequestParam("files") MultipartFile[] images,Model model) {
         return "upload";
    }

форма

<form method="post" action="/postupload" enctype="multipart/form-data">
          <input type="file" name="images" multiple class="form-control" accept=".jpg, .jpeg" >
         <button type="submit" >Upload</button>

    </form>

Если убрать @RequestParam("files") MultipartFile[] images, то ошибки нет. Почему выходит ошибка?