Called about lawsuit filed against me by the IRS. How can I stop these calls?

I got the same message. So weird!

Called about some IRS lawsuit. Its a scam. Don't give out any personal. Hang up the call.

Got the same call, there has to be a way to stop these guys from calling.

There is, but you've got to be able to completely stop these crooks from getting ANY kind of answer when they call. That's mandatory for them being able to leave their bogus threats. A number that only rings becomes worthless to them and one they're likely to quit messing with after some time. If you can't do that, a call blocker might be the best way.