You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

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

ASSISTANT: Sure, I am here to help you with that.

USER: Thank you.

ASSISTANT: May I know your name?

USER: My name is Brian Lopez.

ASSISTANT: Please wait for a minute.

USER: Sure, take your time.

ASSISTANT: We are regret to say that, there is no reservation found on your name in our database.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for reaching us.