Doctor's office to confirm an appointment.
If they're your doctor then it's not a scam call. If they're not your doctor then they dialed the wrong number.
It is an automated message service though so it might sound like a scam.

Yes, this was a robot call to confirm a doctor's appointment. I did not appreciate having it wake me up at 8:00 on Sunday morning! The people who operate this service need to apply some critical thinking to the way they set it up.