AlpsWizard I understand you, but sadly as I wrote Android does not allow this anymore.
If I don't turn the screen on you don't see the popup at all. Android does not show it even if I am calling it.
Sadly I didn't find any workaround because Android controls this since Android 10.
On Android 10 Google does not allow to show a popup from the background anymore.
Only if the app is already open.
The only option was to send it as "High Priority" and turn the screen on.
In this case it works, but in all other cases Google does not allow a popup from the backup anymore :-(