You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Myself Michael Smith.

ASSISTANT: How can I help you?

USER: Due to some reason, I am unable to travel on my previous dates. Can you change my reservaion?

ASSISTANT: Sure, please wait fro a while.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found by your name.

USER: It's ok.Thank you for the information.

ASSISTANT: Thank you and have a nice day.