You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Gary Garcia.

ASSISTANT: How can I assist you?

USER: Owing to an urgency, I would like to cancel my recent reservation to Dallas. Will you help me with this?

ASSISTANT: Sure, I'll help you in that. Please wait for a while.

USER: Sure, I will wait for your response.

ASSISTANT: Gary, there is no reservation found under your name to do cancellation.

USER: Ok, not an issue. May be my brother has already cancelled my reservation on behalf of me. Thank you for guiding me.

ASSISTANT: Thank you for choosing us.