You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Jason King.

ASSISTANT: How may I serve you today?

USER: I need to change my recent reservation due to postpone of my exam. Could you please help me?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please wait for few minutes.

USER: Sure.

ASSISTANT: There is no existing reservation find on your name in our records. Thank you for approaching us.

USER: No problem, thank you for your information.