You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you?

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

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

USER: Lisa Johnson.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

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

USER: No worries, thank you.

ASSISTANT: Thank you for approaching us.