You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am Mary Phillips. I would like to cancel my recent reservation because my trip dates are postponed, can you help me?

ASSISTANT: Sure, please wait a minute.

USER: Ok, take your own time.

ASSISTANT: Sorry Mary, there is no active reservation found under your name.

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

ASSISTANT: Most welcome.