For instance, suppose I am a Vonage customer with phone number 212-555-1234, then decide to leave Vonage and port the number to AT&T. Any non-Vonage customers can still dial 203-555-1234 and reach this AT&T owned number. However, any current Vonage subscribers that attempt to dial this ex-Vonage phone number (now AT&T) receive an error message that says, "That Number Is No Longer In Service."
The customer is pretty upset as evident by his email:
Now that Vonage has ceased billing me and my new telephone company has control of my phone number, there is one legacy Vonage insult left. Vonage now blocks access to your phone number from any of their current subscribers. Any non-Vonage phone can call me, but nobody with a Vonage account can. And I am not alone. I have 5 friends who have suffered this Vonage sneak number block too. My wife is furious, she cannot receive calls from several of her friends. Anyone calling my phone from a Vonage account gets the message "That Number Is No Longer In Service."
Vonage is the devils phone service.
Now I will say that this may not be vindictive on the part of Vonage. This could simply be a database management issue. When a customer leaves Vonage and ports their number, their procedures should include deleting the phone number from their database. I should mention that I'm sure Vonage tries to leverage their SIP registrar database for call routing. So when you dial from Vonage user to Vonage user, it does a SIP registrar lookup, sees both are in the SIP registrar and routes the call over IP and not the PSTN. So perhaps Vonage deleted his record from the billing database but not the SIP registrar. When a call is attempted and his number is still in the SIP registrar, the billing database probably tells the SIP gateway to return the "That Number is No Longer in Service" message. Though usually the billing (usually RADIUS) system is consulted first, so the above explanation could be the reverse.
Obviously, when a Vonage customer cancels, both the billing and SIP registrar should both be updated. Since this customer was porting a phone number to another carrier, perhaps Vonage keeps the record open until they are sure the number has been ported successfully and then forgot to update after a few weeks.
Still, I'm hesitant to make excuses for Vonage and this does stink to high heaven. Perhaps this particular customer just needs to just call Vonage and ask them to delete his phone number record so current Vonage customers can call his phone number. Of course, we all know the trials 7 tribulations when calling Vonage customer service, don't we?
Maybe he'll be joining this Vonage protestor?
p.s. I asked Vonage for comment via email but did not receive a reply within 4 hours. If they do respond I will update this post accordingly.