You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Jeffrey Jackson.

ASSISTANT: How may I aid you?

USER: I had planned to go on a trip, but it was postponed.Can you change my recent reservation?

ASSISTANT: Yes, I will help you.

USER: Ok.

ASSISTANT: I have failed to search a reservation on your name. Sorry.

USER: That's Ok.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your help.