You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you?

USER: I am Lisa Jackson, I want to cancel my reservation as my plan to meet my sister is cancelled. Can you help me to cancel my ticket?

ASSISTANT: Sure, Please wait a second.

USER: Sure.

ASSISTANT: Your ticket has been cancelled, As you requested.

USER: Thank you for your help.

ASSISTANT: Thank you for choosing us.