You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I would like to cancel my flight reservation as my trip got postponed, can you please help me?

ASSISTANT: Sure, we are here to help you. May I know your name please?

USER: Thank you. I am Samuel White.

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

USER: That's ok, thank you for checking.

ASSISTANT: Thanks for contacting us.