You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: As my manager did not approve my leave, I would like to change my recent reservation. Can you please help me out with that?

ASSISTANT: Sure, may I know your name?

USER: Thank you for accepting my request, I have reserved it on the name of Frank Baker.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Oh! I think the ticket was not booked due to server issue. Anyway, thank you for the information.

ASSISTANT: Thank you.