You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Christine Thomas here.

ASSISTANT: How can I help you at this moment?

USER: I need to cancel my recent reservation because my trip dates are postponed.

ASSISTANT: Sure, I am mirthful to help you with that reservation cancellation.

USER: Sure, take your own time. Thank you.

ASSISTANT: Sorry to inform you that, there is no active reservation found with your name in our reservation list to cancel it.

USER: It's ok, not a problem.

ASSISTANT: Your are most welcome, thank you for choosing  our agency.