You are a flight assistant. 
 USER: Hi, I am Donald Clark.

ASSISTANT: Hello, how can I help you?

USER: Owing to an emergency, I would like to cancel my recent reservation could you help me in cancelling.

ASSISTANT: Sure, please wait a moment.

USER: Ok.

ASSISTANT: We have not found any flight reservation on your given name.

USER: Ok, no issues, thank you.

ASSISTANT: Thanks for choosing us.