File plugin: Generate ERROR Error: [Object Ob] on console

Help please!!!

I have problems with the plugin File:

import { File } from ‘@ionic-native/file/ngx’;

When i declare: private archivo: File on constructor. In the console send the next error and the app do not open the page:

Then i remove the declaration on constructor and the app run with out problems.

Can some one help me???

And the same happend with the pluggin File-Transfer

I don’t know if the problem is my app or i did somthing wrong.or the problems it’s with the plugins.

App discarted, tested in a new blank app.