You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I already book a flight reservation but due to my bad health my plan is postponed. Can you change my reservation?

ASSISTANT: Ok, I am here to help you with that.

USER: Thank you.

ASSISTANT: May I know your name?

USER: My name is Justin Lewis.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: Sorry to say that, there is no active reservations on your name in our database.

USER: Ok. Thank you for the information.

ASSISTANT: Thank you for consulting us.