You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I guide you today?

USER: I am Karen Martinez. Please help me with changing my reservation.

ASSISTANT: Sure. Please stand by, I will check in the reservation list and revert to you.

USER: Ok.

ASSISTANT: Thanks for being patient. Sorry, there is no active reservation found on your name in our system database.

USER: Fine, thanks for the information.

ASSISTANT: Thank you for availing us, hope to see you again.