You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you?

USER: I want to change my existing reservation owing to an emergency.

ASSISTANT: Sure, please help me with your name to check your reservation details in our database.

USER: My name is Richard King.

ASSISTANT: Thank you, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, I did not find any reservation by your name in our database.

USER: Thank you.