You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Can you help me in changing my recent reservation?

ASSISTANT: Ok, please can I know your name?

USER: I am Catherine Harris.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry, the reservation you have asked for is not available in our records to amend.

USER: Its ok, thank you.

ASSISTANT: Thank you for choosing our agency.