Push-Notifications at Android app are deactivated on account setup

When connecting to the server (NC 17.0.2, Talk 7.0.2) with the android app (Version 7.0.8), a short information “Push-Notification deactivated” is shown on the setup of a new account.

Using the iOS-app for the same server, push notification works as expected.

Does anyone know if I need some further configuration to activate push notification or to prevent it from being deactivated on account setup?

If you need further information from my side, please let me know.

Problem solved: The f-droid version of the talk app does not provide push notification. For push notification, one has to use the version from Google playstore.