You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Joshua Jones here.

ASSISTANT: How may I assist you?

USER: I would like to change my recent reservation because my trip dates are postponed .

ASSISTANT: Sure, I am here to help you. Please wait a moment, I will check your reservation status.

USER: Sure.

ASSISTANT: Jones, no reservation has been found on your name in our records.

USER: Oh! not a problem.

ASSISTANT: Thank you for approaching us.