this is Rackspace.com a website hosting service. they also have webmail service AND ICLOUD SERVICE. they are probably calling to verify information or to followup on your account. if you don't have a rackspace account then someone gave them your number by accident.
Calls numerous times at all times of day and night and does not leave message. Inadvertently picked up phone today and they said they were ACS. Told them I was on Do Not Call list and her reply was ok and kept talking. I finally said do you even know what that means and she hung up.
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