You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Barbara Thomas.

ASSISTANT: How may I assist you?

USER: I want to cancel my recent reservation due to sudden change inn my trip. Can you help me?

ASSISTANT: Sure, I will help you.

USER: Ok.

ASSISTANT: We found a reservation, shall I cancel your reservation?

USER: Yes you can.

ASSISTANT: Your reservation has been cancelled.

USER: Thank you.

ASSISTANT: Thank you so much.