Upload multiple files using formidable and vue js

Hey guys i am trying to make an app in which i neeed to upload multiple files but in my node backend when i try to upload files using postman it works but while using with vue js it does not work

this is my node backend where i use formidable and try to upload images

app.post('/multiple', (req, res) => {
  var form = new formidable.IncomingForm(),
    files = [],
    fields = [];
  form.on('field', function (field, value) {
    console.log('fields is', field);
    fields.push([field, value]);
  });

  form.on('file', function (field, file) {
    console.log('i came inside file');
    console.log(file.name);
    const oldPath = file.path;
    const newPath = path.join(__dirname, 'uploads/' + file.name);
    const rawData = fs.readFileSync(oldPath);
    console.log('old path', oldPath);
    fs.writeFileSync(newPath, rawData);
    console.log('file uploaded');
    console.log(JSON.stringify(field));
    files.push([field, file]);
  });
  form.on('end', function () {
    console.log('done');
  });
  form.parse(req);
  console.log(files);
  return res.json(files);
});

and this is my vue js front end component code

this is html code for vue js

<template>
  <div>
    <button @click="items++">Add One More File</button>
    <form @submit.prevent="handleImageUpload">
      <div v-for="item in items" :key="item">
        <input type="file" @change="handleFile($event, item)" />
      </div>
      <input type="submit" />
    </form>
  </div>
</template>

and this is script tag for component

<script>
import axios from 'axios';
export default {
  data() {
    return {
      items: 1,
      files: [],
    };
  },
  methods: {
    async handleImageUpload() {
      try {
        const fd = new FormData();
        this.files.map((index, file) => {
          fd.append(index, file);
        });
        const { data } = await axios.post('http://localhost:5000/multiple', fd);
        console.log('data from backend is ', data);
      } catch (error) {
        console.log(error);
      }
    },
    handleFile(e, item) {
      console.log(e);
      this.files[item - 1] = e.target.files[0];
    },
  },
};
</script>

now what happend when I request backend with form data everything goes undefined there