I have had the unfortunate occasions to deal with the IRS and they do not call you at home on Saturday or Sunday and leave a recorded message. You will get multiple notices and certified mail first, you will be asked to go to the local main office, than they may call or come visit you directly at home or the office. This is a scammer and forwarding their number to the IRS:
https://apps.irs.gov/app/scripts/exit.jsp?des ... port_scam.shtml