You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I am Elizabeth Young. Owning to an emergency, I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Please wait for some time.

USER: Sure.

ASSISTANT: Sorry to say this, no reservation found on your name in our database.

USER: Ok, no issues.

ASSISTANT: Thank you for opting us.

USER: Thanks for checking.