Called and left no message.  Return call goes to a full mailbox message.  Scam.

3 calls in the past 24 hours.  Didn't pick up, left no message.  Caller ID: NEW YORK CITY O.

Called several times.  Name comes up on caller id as NYC.  Caller claims to represent National Grid offering a cash back for customer loyalty.  Asks for national grid account number.   Calling center obviously coming from India given the rep's accent.  Seems like a scheme to switch provider services or some other scam.   Best to not answer or just hang up.