Customer was upset I didn’t ask for his account number

Customer called, I asked his name (unique, definitely not a Bill Smith) and verified the address.

Call proceeds apace, he wanted an increase to his credit limit, which was denied. He goes ballistic and berates me for not asking for his account number.

$me: “Do you know your account number, sir?”

$cust: “NO!”

$me: “That’s right, because those are for internal use only. I can give you your account number, it’s not a secret, but knowing it isn’t going to do anything for you.”

$cust: “YOU DIDN’T ASK ME FOR MY ACCOUNT NUMBER! YOU’RE A SCAM!”