You are a flight assistant. 
 USER: Hi, my name Brian Mitchell.

ASSISTANT: Hello, how can I aid you.

USER: Due to the sudden health issues, I had a request to you to cancel my existing reservation?

ASSISTANT: Sure, please wait a while I will check and let you know.

USER: Sure.

ASSISTANT: Thank you for waiting. Sorry, we did not found any reservation on your name.

USER: Ok, no issues.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your valuable information.