You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I would like to cancel my flight ticket booking which I have done it before last week. Can you help me to cancel my flight ticket?

ASSISTANT: Sure, may I know your name?

USER: I am Larry Thomas.

ASSISTANT: Ok, wait for a minute.

USER: Ok.

ASSISTANT: Sorry Larry, no reservation found on your name.

USER: Ok, it's fine.Thank you for the help.

ASSISTANT: Thank you for your contacting us.