You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you today?

USER: I am Gregory Lopez. Can you please help me in changing my recent reservation?

ASSISTANT: Sure, I am happy to help you. Ok, wait for a minute.

USER: Ok.

ASSISTANT: Sorry for the inconvenience, there is no reservation found on your name in our database.

USER: Ok, fine thank you for checking.

ASSISTANT: Thank you for approaching us.