Got a call from 602-973-8212.  Sounded like voices talking in the background, but no one answered when I kept saying "Hello".

Called the number back and got a recording that the number is not in service or is in another area code (even though I dialed the area code as well).

Call came in with ID M. Miller. Left no message. I called back and the line was busy

caller ID said M Miller. I did not get the call in time and when I tried to call back, no ring or anything. I hate these pesky harrasing phone calls.

Caller id said M Miller.
I answered and a recorded msg said sorry that I was called in error.

Got a call, answered and it sounded like voices talking in the background but no one answered when I kept saying "Hello"

Called back, rang twice and said number is not in service or is in another area code (even though I dialed the 602 area code as well).

Same here.. It just rings then nothing..

tried to call back # - recording says # not in service or is in a different area code.

Call, but never leave a message! Why even bother to call if you don't have anything to say. It says M Miller on the caller ID