You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, will you please share your name?

USER: Karen Robinson.

ASSISTANT: Ok, please wait.

USER: Sure.

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

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.