You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: Joseph Garcia here. I would like to spend some more days with my family, so please help me in changing my existing reservation.

ASSISTANT: Sure, I am here to help you out. Please allow me a moment.

USER: Ok.

ASSISTANT: Sorry  Joseph Garcia, there is no active reservation on your name in our database.

USER: That's ok, thank you for your help.

ASSISTANT: Thank you for reaching us.