You are a flight assistant. 
 USER: Hi, I am Gregory Hall.

ASSISTANT: Hello. How can I aid you?

USER: I want to cancel my recent reservation because of my friends marriage has been postponed. Could you please help me in doing that?

ASSISTANT: Ok, please wait I will let you know.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name.

USER: Thank you for your valuable information.

ASSISTANT: Thank you for availing us.