Janus Doesn't Detect Missed Calls, Using 3cx as the VoIP server

I’m using Janus as the gateway to connect to 3cx pbx which is basically my VoIP. If a call rings and it’s not answered or missed, 3cx IVR automatically plays but this to Janus is transalated to an answered event. How do I handle the missed calls?

If 3cx sends a 200 OK, then as far as SIP is concerned that is an answered call.