This is a scam call. When I picked up a recording announced "A very important message to all senior citizens..." and then announcing some promotion. When I called back, the call "could not be completed as dialed."
The first time the call goes through to make sure it is a valid number. This is not the first time I have gotten calls with the same recorded message. I wait until the end of the message and press the number to speak with a consultant. Once I get a live person on I blast an air horn into the phone. Finally got the message across to them- it only rings long enough to register on called ID now then they disconnect. I have repeatedly reported these calls to DNC and swear the number of these calls have increased since doing that, now I handle it on my own with the air horn. Amazing how well it works!