Edx app android can't show course content

I have a problem with the android app. I can access course’s videos but text and quiz returns me a 404 not found error.
I didn’t have this problem on native installation. So i debugged the app.
I discovered that that this url and view

# OAuth token exchange
   urlpatterns += [
       url(r’^oauth2/login/$’, LoginWithAccessTokenView.as_view(),

use dot_models (Django Oauth Toolkit) to validate the user, but in the database the tokens are localted at /admin/oauth2/accesstoken/ not at /admin/oauth2_provider/accesstoken/.But i have ENABLE_OAUTH2_PROVIDER enabled.
what is going wrong ?