You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How exactly I can serve you the best today?

USER: Could you please help me to update my travelling dates in my existing reservation as my trip dates got postponed?

ASSISTANT: Sure, I can change your reservation right now. Before that I need to know your good name please?

USER: I made a reservation by this name Patricia Martin.

ASSISTANT: Ok, wait for some time I will check the reservation on your name and get back to you.

USER: Sure.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: That's ok, no problem. Thank you for your information.

ASSISTANT: Thanks for approaching us, wish you a great day.