No, the IRS is not calling you, scammers are calling you. The IRS will contact you by US Mail if there's a problem and they won't threaten you with a lawsuit. This is a scam, plain and simple. Just block and ignore their calls.
This is absolutely a scam. I called the IRS with the gentleman's supposed "badge number" (850019, which is way too short to be an IRS badge number), and they confirmed he does not work there. His name was "Derrick Johnson." His direct extension is 1812. Absolute tool on the phone--aggressive and mean. No one I have ever spoken to at the IRS has been anything but kind, helpful, and calm. DO NOT GIVE THEM MONEY. THIS IS A SCAM. If the IRS calls you, they will not use an automated system, and they always call from 1-800 numbers. They also NEVER require you to spend money immediately. They always give you a window of time or set up a payment plan with you. This is utter and terrifying [***].