Hi Desire Skills,
This can easily be done on our platform (based on freeswitch). You can design call routes to reach a users VM directly without ringing any other devices.
We provide white labelling service for our platform. We can discuss more about this if you're interested.
My initial questions are:
1. What is your and your business' name?
2. Do you have a requirement of ringless VM to be deployed immediately?
3. Do you also have other requirements for VoIP?
Thanks,
Varun S.
Merit-Tel, LLC.