cuando envío el formulario al botón Enviar formulario , todo funciona y el archivo cargado se registra en la consola del servidor, pero ¿por qué aparece el error Multipart: Límite no encontrado cuando hago clic en Enviar usando buscar ?

 const express = require("express"); var bodyParser = require("body-parser"); const app = express(); const multer = require("multer"); const fileStorageEngine = multer.diskStorage({ destination: (req, file, cb) => { cb(null, "./images"); }, filename: (req, file, cb) => { cb(null, Date.now() + "--" + file.originalname); }, }); const upload = multer({ storage: fileStorageEngine }); app.use(bodyParser.urlencoded({ extended: true })); app.use(bodyParser.json()); app.use(bodyParser.text()); app.get("/", (req, res) => { res.send(` <form action="/push" method="POST" enctype="multipart/form-data"> <input type="file" name="image" /> <button type="submit">Submit form</button> <button onclick="send(event)" type="submit">Submit using fetch</button> </form> <script> function send(event) { event.preventDefault(); let formData = new FormData(event.currentTarget.parentElement); fetch("/push", { body: formData, headers: { "Content-Type": "multipart/form-data", }, method: "POST", }).then((data) => console.log(data)); } </script> `); }); app.post("/push", upload.single("image"), (req, res) => { console.log(req.file); }); app.listen(3000);