Integration fail with UserNotAuthorizedException error on Android

[ndthong1994]

I have integrated on Android Platform like quick sample on document,But I got the "com.spotify.android.appremote.api.error.UserNotAuthorizedException: {"message":"Explicit user authorization is required to use Spotify. The user has to complete the auth-flow to allow the app to use Spotify on their behalf"}"  when conntect with the remote app at

SpotifyAppRemote.connect()

. How can fix it?.Please!