Capacitor + Quasar + VueJS2, download files in Android

Good Afternoon everyone,
I need help for my Android app:
I’m trying to install and use correctly the FileSystem Plugin, because I need to download files.
Here’s my problem:
I don’t knwo how to save that file in android, how can I do that?
I’m using Quasar + Capacitor + Vuejs 2.

Following my code

methods in my Page:

getDropboxFile(dropboxFileId, dropboxFileIdRootAnnex) {
console.log('download')
  const self = this;
  axios({
    url: 'myurl' +
      dropboxFileId +
      '/' +
      (dropboxFileIdRootAnnex != null ? dropboxFileIdRootAnnex : '-'),
    method: 'get',
    responseType: 'blob',
    showInCatch: 'true',
    headers: {
      Authorization: self.$store.state.token,
    },
  })
    .then(function(response) {
      console.log('sono nella response')
      let fileName = response.headers['content-disposition'];
      var FileSaver = require('file-saver');
      var blob = new Blob([response.data]);
      FileSaver.saveAs(blob, fileName);
      
      var path =  "Download/" + fileName;
      writeFileAndroid(blob,path);
      // writeFile(options: WriteFileOptions) => Promise<path>;
    })
    .catch(function(error) {
      console.log('error A1')
      console.log(error)
    });
},

const writeFileAndroid = async (blob,path) => {
  console.log('dentro writeFileAndroid')
    let args ={
      path: path,
      data: blob,
      directory: Directory.Documents,
      encoding: Encoding.UTF8,
    }
    await Filesystem.writeFile(args);
    console.log('post await')
};

MainActivity.java:

public class MainActivity extends BridgeActivity {

@Override
public void onCreate(Bundle savedInstanceState) {
// Initializes the Bridge
this.init(savedInstanceState, new ArrayList<Class<? extends Plugin>>() {{
// Additional plugins you’ve installed go here
// Ex: add(TotallyAwesomePlugin.class);
add(Filesystem.class);
add(Storage.class);
}});

super.onCreate(savedInstanceState);

}
}

what am I doing wrong?
Thank you for help!