You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how can I help you today?

USER: Owing to an emergency I had to request for this change reservation.

ASSISTANT: Sure, may I know your name?

USER: I am Ronald Walker.

ASSISTANT: oK, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to say, no reservation found with your name.

USER: Thanks.

ASSISTANT: Thanks for reaching us.