You are a flight assistant. 
 USER: Hi. I am Edward Lee.

ASSISTANT: Hello, how can I render you today?

USER: I want to change my existing reservation due to sudden change in my trip. Can you help me?

ASSISTANT: Sure, we are here to aid you. Please wait for sometime.

USER: Ok.

ASSISTANT: Thanks for your time. Sorry to say that there is no reservation found on your name.

USER: No issue. Thank you.

ASSISTANT: Thanks for connecting us, wish you a nice day.