title: FormData sends empty data using axios
body: <p>I want send my data from vue to api. I don't know why my formData is empty. You can see snapshot attached. I've tried several hours using several links on stackoverflow <a href="https://stackoverflow.com/questions/53555705/axios-formdata-getting-empty-object">this link</a> and <a href="https://stackoverflow.com/questions/49587831/how-to-append-files-and-data-to-formdata-in-vue-js">this link</a>.</p>
  
  <p><a href="https://i.stack.imgur.com/SJunk.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SJunk.png" alt="enter image description here"></a> </p>
  
  <p>my confirm method:</p>
  
  <pre><code>async confirm () {
        let formData = new FormData()
        let params = {
          name: this.product.name,
          department_id: this.departmentId,
          category_id: this.categoryId,
          sub_category_id: this.subCategoryId,
          brand_id: this.brandId,
          weight: parseInt(this.product.weight),
          unit_weight: this.product.unitWeight === 'gram' ? 'g' : 'ml',
          volume: {
            length: parseInt(this.product.volume.length),
            width: parseInt(this.product.volume.width),
            height: parseInt(this.product.volume.height)
          }
        }
        formData.append('file', this.imageFile)
        formData.append('data', JSON.stringify(params))
        console.log(formData.getAll('data'))
        console.log(formData.getAll('file'))
        console.log('this.imagefile', this.imageFile)
        console.log('this.params', params)
        console.log('formData', formData)
        this.fullscreenLoading = true
        await this.klikdailyAPI().post('products', formData).then(result =&gt; {
          let message = this.product.name + ' succesfully created'
          this.$store.commit('products/setMessage', message)
          this.$router.push('/products')
          this.fullscreenLoading = false
        }).catch(err =&gt; {
          this.snackbar = true
          this.snackbarObject = {
            color: 'error',
            text: 'ERROR! ' + err.response.data.message
          }
        })
      }
  </code></pre>
  
  <p>my api method:</p>
  
  <pre><code>klikdailyAPI () {
        return axios.create({
          baseURL: `${url}/api/v1/`,
          headers: {
            'Authorization': `Bearer ${localStorage.getItem('tokenApi')}`,
            'Content-Type': 'multipart/form-data'
          }
        })
      }
  </code></pre>
  
  <p>What's wrong with my code? </p>