Nomorobo Max allows you to send a Practice Call, letting you see exactly what happens when an unknown call is screened.
In Status, tap Send Me a Practice Call.
You'll receive a Screened Call push notification that looks like this:
TIP: If you don't see the push notification, try toggling Airplane Mode On then Off, then try the practice call again.
When you tap the notification you'll be able to see how Nomorobo Max screens the call in real time. You can read a Transcription and listen to the Call Screening Audio.
Then decide between three options: Allow This Call, Send to Voicemail, or Hang Up Call. If no option is selected the call will automatically be sent to voicemail after 80 seconds.