"Notify Missed calls" option is missing

I’ve seen in some topics and in the Wiki as well that the missed call notification for extension is implemented. My problem is that this option is missing from my VitalPBX 4. I use free version.
PBX engine is 18.23.1
VitalPBX version is 4.1.0-6

See attached screenshots.

Where is this option? Do I need to enable addon? Do I need to purchase licence?

image

This feature is only available for the Starter license and subscriptions.