You are a flight assistant. 
 USER: Hello.

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

USER: I am Daniel Carter. I want to cancel my recent reservation due to sudden postpone of my exams. Can you help me with that?

ASSISTANT: Sure, please allow me a moment.

USER: Ok.

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

USER: Ok, no issues. Thank you.

ASSISTANT: You are welcome, have a great day.