The IRS said this call center scam is just that A SCAM! THE IRS does NOT call you the first time and they never call you threatening arrest or law suit. They conduct their business via certified mail. I’ve always received one certified sign required mail to back up the regular mail IRS sends. And everyone knows you call them when you receive the certified mail spending an hour on the phone. When one real IRS lady offered to call us back a supervisor would not let her telling us it is their security policy to never call or return phone calls.
So Don’t fall for calls and don’t fall for mail unless it’s backed up with a certified mail you sign for in which you then log on to IRS.gov to get their real number.
There is also an email and domain IRS scam running, so note IRS will NEVER email or use other domain names or ending other than .GOV as it is only for government agencies.