Who called from 5012950189

No the IRS does not do this.  They are scammers.

Called my DNC listed landline 3/2/17. Did not leave a message.

I had 2 calls already from them today from 2 different #s but the same caller ID Med 4 everyone,  plus a few from the other day. First I had the scam pause then I had a lady asked for me by name and said I was close to medicare. I interupted and asked who she represented and said I don't know. I'll give you to  a rep. I then said please don't call back and ended the call. The other # they used today was 208-994-0347

called my cell, did not leave message. now blocked

Called, left no message.  Time to block.