You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you now?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, may I know your name please?

USER: Myself Jessica Mitchell.

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

USER: Ok, fine not an issue. Thank you for checking.

ASSISTANT: Thank you for reaching us, have a nice day.