You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you today?

USER: I am Donald Lee. I want to change my recent reservation due to emergency work. Can you help me with it?

ASSISTANT: Sure, please wait a moment.

USER: Sure.

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

USER: That's fine, thank you for your effort in checking my exiting reservation.

ASSISTANT: Thanks for reaching us.