"Hi NAME, NAME is currently unavailable"

**all names changed for privacy**

So ever since I switched to AT&T, there has been one glaring issue. Everyone thinks I'm this girl named Pam when really I am this girl named Laura. When I call someone else who has AT&T, and they don't answer, my phone screams "HI PAM, GEORGE IS UNAVAILABLE" at 7 billion decibels and I can't help but feel like that would be a little less annoying if they were saying my name instead of someone else's name. I also get a million phone calls from Pam's lawyers saying she isn't answer her mail or other phone so that's nice. How do I change the name?