form-data in Postman does not work but raw json does

I'm facing some problem when making a POST request. It works when I send raw data in JSON(application/json) format, but doesn't work when I send in form-data from Postman. I tried using multer but I am not sure if I did it right, so feel free to point that out too. Following is the screenshot of result from the Postman:

Here's the Mongoose Schema:

const mongoose = require('mongoose');

const ItemSchema = mongoose.Schema({
    title:{
        type: String,
        required: [true,'Please enter a title for the item']
    },
    description:{
        type: String,
        required: [true,'Please enter a description for the item'],
    },
    image: {
        type: String,
        // required: [true, 'Please add an image for the item'],
    }
});

// Uploading an image to the server and getting shareable url
ItemSchema.pre('save', async function (next) {
    const file = this.image;
    console.log(file);
});

module.exports = new mongoose.model('Items',ItemSchema);

Here's the post request from the controller:

exports.createItem = asyncHandler(async (req, res, next) => {
  const item = await Item.create(req.body);

  res.status(201).json({
    success: true,
    data: item
  });
});

The routes are defined in a separate file as follows:

const express = require('express');
const multer = require('multer');
const { getItems, getItem, createItem, updateItem, deleteItem } = require('../controllers/itemController');

const router = express.Router({ mergeParams: true });
const upload = multer();

router
  .route('/')
  .get(getItems)
  .post(createItem,upload.any());

router
  .route('/:id')
  .get(getItem)
  .put(updateItem)
  .delete(deleteItem);

module.exports = router;