You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello,.

USER: I am Brian Smith.

ASSISTANT: How may I assist you?

USER: I just want to cancel my recent reservation due to ongoing tornado at my destination point. Can you help me?

ASSISTANT: Sure, please wait a while.

USER: Ok.

ASSISTANT: Thanks for your time.

USER: My pleasure.

ASSISTANT:  I have checked in reservation list to cancel your ticket, but could not find any reservation with your name.

USER: Thanks for your prompt response.

ASSISTANT: Thanks for your presence.