You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you now?

USER: Due to emergency meeting, I just want to change my recent reservation. Can you please aid me to change it?

ASSISTANT: Sure, I will help you to change your reservation. May I know your good name?

USER: Sure, Robert Miller is my name.

ASSISTANT: Please wait for a while and let me search for your reservation in our system data.

USER: Sure, I will wait for your response.

ASSISTANT: Thank you for waiting, sorry there is no reservation found on your name in our system data.

USER: Ok, no problem. Thanks for your assistance.

ASSISTANT: Thank you for visiting us, we hope see you again.