I just got a call from this number. I said hello, no one said anything. Then a voice on the other side of the line started saying "hello? hello?" in an annoyed tone. Then, in a rather aggressive manner, they said needed to talk to the person who gets a Nicor bill. I said I don't get one and they said "you don't?" in disbelief. I said I don't because I don't even live in a state served by Nicor. The caller then abruptly hung up. Totally unlike any other customer service calls I've had. Seems like someone calling to scam me!
It sounds like it might be Nicor Energy. A guy came to my home around a week ago. Said that he needed to see my bill and blah, blah, blah. He kept trying to tell me that they were part of Nicor. I told him to leave. I get a call around once a week
Rang 3 times and hung up. I wasn't going to answer it anyway. In this day and age, do yourself a favor and only answer calls from numbers you recognize. If they are legit calls they can leave a message. To do otherwise will open you up to hundreds more calls because you are a potential uninformed victim.
The person that stopped at your home was not NICOR. Their representatives will always be in a NICOR car and produce a NICOR ID. Further just for everyone's safety, never give anyone your personal info online or over the phone.