You are a flight assistant. 
 USER: Hello. I am Barbara Brown.

ASSISTANT: Hello, how may I serve you at this moment?

USER: I would like to change my reservation as I am leaving for delegates meet, can you please help me out?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry, no reservation has been found with your name in our database.

USER: Ok no problem, thank you for your services.

ASSISTANT: Thank you for reaching us.