I got these calls for a while, they stopped and now started up again. I get a voicemail saying "Hello, this is a service verification. We will call you back later, thank you". Based on what I've read from others it sounds like scammers.
I've been getting a phone call everyday for the past few days from this number. The only message they leave is that they will call back later, no identification of who it is or any reason why they're calling. That leaves me assume it's some kind of scam/solicitor.