更新对象时返回404错误

updateFileName: function() {
    var files = this.data.files
    const editor = this.data.editor
    const file = files[editor.index]
    if (editor.title) {
      const fileObj = AV.Object.createWithoutData('_File', file.object_id)
      fileObj.set('name', editor.title)
      fileObj.save().then(res => {
        files[editor.index].name
        this.setData({
          files: files
        })
        this.closeEditor()
      }).catch(err => {
        this.closeEditor()
      })
    }
  }

更新文件对象时,返回:404,Not Found 错误
但服务端确实是有存在这条数据,这我就懵了