1. If none of the above steps help, it is possible that you are not receiving updates from Google’s push notification service.
    • Test if it is working with the app Push Notifications Fixer from the Google Play Store.
  2.  Edit your VPN or firewall settings.
    • Android phone Settings > More (Under Wireless & Networks) > VPN then disable Wi-Fi Assistant.
    • Make sure you allow *.whispersystems.org, TCP ports 80, 443, and 31337, and all UDP. If you have a transparent or reverse proxy it needs to support Web Sockets.
  3.  Reset your Google Account.
    • Android phone Settings > Applications > Manage applications > All (Swipe right on some phones for this list, if not listed in Downloaded).
    • Choose Google Play services > Clear data.
    • Choose Google services framework > Clear data.
    • Temporarily unlink your Google account from the phone.
    • Reboot the phone.
    • Re-associate your Google account.