You cannot receive calls through Wazzup, so any call will be missed. A message about an unsuccessful call from a client will come to the Wazzup chat and to the CRM chat.
If you yourself drop the incoming call from the phone, then the message about the missed call will not come.
The message will come to the CRM chat in the form “=== SYSTEM WZ === Missed call”.
Missed call message in Wazzup chat