Just ring up again. You'll get someone else. The call center couldn't have only 1 person answering the phone. If they ask you a question you don't know the answer to, tell them the truth.

I've been asked, what's the address on the statement? I told them I can't remember if it's my house or office, so I gave them both.

I've also been asked how much was the last payment on the credit card. I couldn't remember. Told them that. Asked them to ask me another question instead.

It's not some game or exam where you have to get every answer exactly right. Just remember their objective. They only want to confirm that you are who you say you are. That's all.