It called me and said just die or good bye I wasn't sure

Recorded message announces some statistics about the number of seniors who fall. I've gotten this call on my cell phone about three times in the last week. Very annoying!

once a week or so, this number calls my cell, if i answer, no ones there. if i dont, it only rings a couple times. i called it back once and a recorded message came on and hung up almost immediatly, cant remember what it said. since i called it back, ive been getting a lot of calls from different area codes asking for "Frank". some local calls as well. Coincidence? i dont know.

I got a call from 775-059-4744 on my cell, i answered & it said "goodbye" in a computer voice. Wtf?

Two rings - I picked up phone - no one online.