You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

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

ASSISTANT: Sure, could I have your name please?

USER: I am Joseph Garcia.

ASSISTANT: Ok, please allow me a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation with your name in our portal to cancel further.

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

ASSISTANT: You are welcome, have a great day.