Who called from 4845895625

They have called me twice today but when I call back to see who they are, the phone says that that number is not in service.  ??????

they have called me also and it sounds like a machine and then a real person picks up and then back to the machine.. i also tried calling back and it says the number is not in service....  ???

if i answer no one is there. when I call back it says not in service.

How can someone call me from a number that's not in service?

Just put them in your reject list (if you have one on your phone)...I did.