Who called from 7049211876

Who is this caller?
Calls me 4 times on Sunday.
I call back but got no answers, phone just rings, rings, rings

received a call Sunday afternoon on my Google voice number, which almost no one has yet.  I missed it, but there was no message, I'll try calling it tomorrow but I have a feeling, I'll have no luck

Call on Tuesday afternoon to Google Voice number. no voicemail left. continuous ringing on callback.

Received a call today about 2:00 pm.  Caller ID indicated "Charlotte Water Sys" and the number 704-921-1876.  Tried to call the number and it would not go through the system.  I do not believe their is a 921 series of numbers as yet!

received a call from 704-921-1876 on 4/24... just once, with no voicemail. called back, it says carolina energy & water