Who called from 6312794100

Called at 11:30 this morning.  The phone was near my hand, so I pressed Talk button, then disconnected instead of waiting to see if they'd leave a message.

called 12:44PM (Miami,FL).  Did not leave a message. Unable to determine if a scam.

Call today, 4 Jan 17, no one spoke.  Hung up after 5 seconds of waiting.

called at 1057 today (Virginia Beach)- no message

Call on 1/5/2017 at 12:28 p.m.  I have only 1 credit card and the phone number that they used is not connected at all to the account.  It sounds like a scam.