You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you today?

USER: Owing for an emergency, I want to change my flight reservation. Can you please help me out?

ASSISTANT: Sure, I will help you with that. Can I know your name to check your previous reservation?

USER: I am Sharon Phillips.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: We regret to inform you that, there is no reservation found on your name in our records.

USER: No problem, thank you for checking.

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