You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you today?

USER: I need to change my reservation due to urgent meeting, can you help me?

ASSISTANT: Sure, I am mirthful to help you with that. May I know your name please?

USER: I am Emily Walker.

ASSISTANT: Please wait for a moment, let me check your previous reservation status.

USER: Sure.

ASSISTANT: Sorry to say that, there is no active reservation found on your name in our database to change.

USER: That's ok. Thank you for your service.

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