You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I amend you today?

USER: I am Jack Lewis.

ASSISTANT: Ok.

USER: Owing to an emergency, I request for this change my recent reservation.

ASSISTANT: Sure, I will help you with that.

USER: Thanks.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Thank you for waiting. I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.