`fileTransfer.download` is not working in iOS 11.4.1

We have video file in mp4 format in our server,and within the application we are rendering the video file and playing in the video player,So now user can also download the video from the server. As the application is build in Ionic platform we are using cordova plugin file transfer plugin and file-transfer npm for downloading the videos,So basically when we start download filetransfer onprogress event is fired and in that we see download percentage 0 and directly 100, and success event is fired for fileTransfer.download and it shows download success,we are downloading the file in locations file.dataDirectory in ios device.When we fetch the video file from the downloaded locations it is unable to play as it is corrupted. We are facing this issue in IOS(11.4.1) device only in android it is working fine.

This is my code for download video file from the server for IOS version(11.4.1)

fileTransfer.download(url, this.file.dataDirectory + 'file.mp4').then((entry) => {
    console.log('download complete: ' + entry.toURL());
  }, (error) => {
    // handle error

ionic version: 3.19.1
node version: 8.11.3
cordova version: 8.0.0
cordova-plugin-file-transfer version: 1.7.1
node module @ionic-native/file-transfer version: 4.11.0
platform Ios version: 4.5.5

I can not upload as well! In Android it works.

I do not receive any error message.

let options = {
fileKey: “file”,
fileName: fname,
chunkedMode: false,
mimeType: “image/jpg”,
params : {}

this.file_transfer.upload(filepath,encodeURI(url), options,false).then((res:FileUploadResult)=>{
Update: I changed the options to:
chunkedMode: true,
mimeType: “image/jpeg”,

and now it works!