You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: My convocation meeting has been postponed.So, I would like to change my existing reservation which is under my  name. Can you please help me with that?

ASSISTANT: Sure, may I know your name?

USER: My name is Jessica Roberts.

ASSISTANT: Sorry, no reservation found Roberts.

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: You are welcome. Thank you for contacting us.