You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: Due to some personal issue, I want change my recent reservation, can you check once is there any chance to change this reservation.

ASSISTANT: Ok, I will you with that. May I know your name to check your status of reservation whether it is existed or not?

USER: Please check with the name Christopher Turner.

ASSISTANT: Thanks for giving your name, please wait a moment, let me check.

USER: Sure.

ASSISTANT: Thanks for your patience, there is no reservation found under your name to change it.

USER: It's ok, anyways thanks for your information.

ASSISTANT: Welcome.