It's say a lawsuit from IRS I'm unknown of why?

Relax, Joyce.  It's a SCAM.  Block the number, ignore any such calls and NEVER answer calls from numbers or persons you don't recognize.
You can read about the IRS scam here:
https://www.irs.gov/uac/newsroom/irs-repeats-warning-about-phone-scams
http://www.forbes.com/sites/johnwasik/2016/06 ... u/#6cb8a18e171f

Called left no message.  Blocking.