I had a similar call today and did not respond to unrecognized number on my call display.
I am averaging two calls a day from unrecognized out of area numbers and it appears nothing can be done to preven them.
Did receive a call from 289-803-0102. I don't pickup calls where the number is unknown to me. They did not leave a message. If somebody wants to talk to you they leave a message to get back to them, if not then it is not important and probably fraud or marketing. Nothing helps to stop calls from comming even though the number is registered under do not call list.
This is a fraud campaign currently active in Canada using a series of Iristel VOIP numbers. The objective is to obtain your credit card number and drain your account.
If you attempt to "opt out" your number will be confirmed as live and added to a suckers list for repeated future calls.