Productive uses Conditional Call Forwarding (CCF) to receive your missed calls and connect you to Productive voicemails.
Metro by T-Mobile has the Call Forwarding feature available for $1 per month. You can add this feature in the Value Package by contacting Metro by T-Mobile Customer Service at 611 or you can add it directly from your MyMetro app.
Once this feature is activated, you can proceed with a Productive install.