this is not the only number they call from. I got the same call a few weeks ago from a 712 area code. The IRS does not use outside sources to collect for them, and they do not contact you by phone. This is a SCAM dont fall for it.
I got a call it said unknown then it was an automated call saying irs is filing a lawsuit and to call back this number.
What's the purpose of this what are they gaining by calling and saying that?