You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Dorothy Wilson.

ASSISTANT: How may I assist you?

USER: As I have a sudden plan change in my schedule, so I would like to cancel my recent reservation to Dallas.

ASSISTANT: Give me a moment, let me check your details.

USER: Ok, take your own time.

ASSISTANT: Wilson, your reservation is successfully cancelled.

USER: Thank you for cancelling my ticket.

ASSISTANT: Thank you for consulting our service.