You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Owing to an emergency, I need to change my reservation. Can you help me with changing my existing reservation?

ASSISTANT: Sure, can I have your name please?

USER: Sure, I am Dennis Davis.

ASSISTANT: Ok, please wait for a while. Thanks for waiting, no flight reservation found with your name.

USER: Ok, no worries.

ASSISTANT: Thank you for choosing us.

USER: Thank you for your information.