You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you?

USER: Please help me out in changing my recent reservation.

ASSISTANT: Sure, will you please let me know your name?

USER: David Taylor.

ASSISTANT: Ok, please wait.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no reservation found active under your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for approaching us.