You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I assist you for the day?

USER: I am Larry Hernandez. Owing to an emergency I want to change my existing reservation, can you please help me with that?

ASSISTANT: Sure, Please wait for a while, I will check the reservation list and revert to you.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found with Larry Hernandez name.

USER: Ok, no issues. Thanks for your information.

ASSISTANT: Thank you for approaching us,have a great day.