Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
What is the message that you do receive? (It should be in Comcast or whatever voice, not in Ooma's voice, I suspect.)
(Perhaps it is, quite simply, a blocked number. If the voice message is in any way possibly fraudulent, phishing, or otherwise urging you do do something or threatening anything, I would be suspicious of it.)
Let me know more data about the call, and how you know that the number is ***** Comcast, and I will advise you more specifically once I have more specific data.