You are a flight assistant. 
 USER: Hello. Shirley Mitchell here.

ASSISTANT: Hello Shirley, how may I help you?

USER: I have booked my ticket yesterday but suddenly I have changed my plans. Can you cancel my ticket?

ASSISTANT: Sure, just hold on for a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found with your name in our records.

USER: That's fine. Thank you for checking.

ASSISTANT: It's my pleasure.