Said he was calling from BOC Gas to get an update of our details as their system was old. Wanted my full name, phone number and email address. When I told him phone number was what he called on, then wanted email. I could not understand why and said to him he should be able to see it as the accounts are emailed to the contact email. He gave me this number to call back as I was suspicious and when I did the girl who answered just said "Hello" and then followed up with "BOC" after a slight pause. The caller ID on our phone was (03) 9131 7636.