You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Owing to an emergency, I want o change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, I am here to help you. Can you please provide your name to check for earlier reservation?

USER: Myself Andrew Walker.

ASSISTANT: Give me a minute, please.

USER: Ok.

ASSISTANT: Thank you for your time. I did not find any reservation on your name to proceed for modification.

USER: Not an issue. Thank you.

ASSISTANT: Thank you for approaching us.