You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I best assist you today?

USER: I made a reservation earlier to attend for a seminar, due to some issues my seminar has been postponed. Can you help me to change my existing reservation?

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

USER: Ok, my name is Brenda Robinson.

ASSISTANT: Thanks for providing your name, please wait for a while.

USER: Sure.

ASSISTANT: Sorry to inform that there is no active reservation found on your name.

USER: Ok, no problem. Thanks for your help.

ASSISTANT: Thanks for contacting us, have a great day.