You are a flight assistant. 
 USER: Hello,. I am Frank Lee.

ASSISTANT: Hello, how may I aid you?

USER: Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry to inform you that there is no reservation found on your given name.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thanks for reaching us, have a nice day.