You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Sarah Green here, want your help to cancel my ticket due to sudden change of our plan, can you please do it?

ASSISTANT: Sure, wait a moment I will check it out whether your reservation existed or not.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found under your name, I think your reservation is not properly done.

USER: Yes, I think so.

ASSISTANT: Thank you for reaching us. Have a great day.

USER: You are welcome. Thank you.