Given the question "What is the caller's number?" and the answer "7683384.", write a conversation that might have happened.


W: Operator, can I help you?

M: Yes. I'd like to make a collect call. My number is 7683384.

W: And the number you're dialing?

M: That's 7638558. Oh, no, I'm sorry, I forgot it's just changed. It's now 7643388.

W: Please hold the line, caller.