You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you at this moment?

USER: I just want to change my existing reservation due to my trip with my friends has been postponed. Can you please aid me to change it?

ASSISTANT: Sure, I am here to assist you with this.

USER: Thank you.

ASSISTANT: Can you please provide your name to check your reservation status?

USER: Sure, Paul Walker is my name.

ASSISTANT: Wait a moment please.

USER: Sure.

ASSISTANT: Paul Walker, there is no active reservation found under your name our database.

USER: That's Ok, thanks for your information.

ASSISTANT: Thank you for contacting us.