How to download multiple files in order in the background.[ios]

I want to download multiple files in the order in the background as the following:

```
_finishDownload(result) {
.........

this._downloadTask();
}

async _downloadTask() {
cont newUrl = getNewUrl();
const options = {
fromUrl: newUrl,
toFile: dest,
background: true,
connectionTimeout: 1000 * 10,
progress: res => this._onProgress(res),
};

const { jobId, promise } = RNFS.downloadFile(options);
promise
.then(result => {
this._finishDownload(result);
})
.catch(error => {
console.error(error);
});
}
```

But I find RNFS cannot start a new download task when the current download task complete when the app becomes background.