This number keeps calling my cell phone.  Does anyone know whom this could be.

I'm getting it too!!  Have no idea!  4 times today!

Same thing happening to me...

It is VESTA CORPORATION. I received a call today and answered it. It says they are representing AT&T and that there is an outstanding balanced owed. Contact AT&T and settle it.

Ok thanks, Not sure why they called I have an AT&T home phone service and cell service, if I had an outstanding bill I am quite sure, neither one of my phones will be on.  Will call them today and find out what is wrong.  Once again, Thanks.