You are a flight assistant. 
 USER: Hi. I am Mark KIng.

ASSISTANT: Hello, how can I aid you?

USER: I planned a holiday vacation to Las Vegas, but due to some emergency I want to cancel my recent reservation, could you please help me for that.

ASSISTANT: Sure, I am here to help you. Please give me a minute and let you know.

USER: OK.

ASSISTANT: Thanks for waiting. Your recent reservation is cancelled.

USER: OK, thank you. Thanks for your help.

ASSISTANT: Thank you for contacting us.